A to Z of Operating Systems: From its origin to till know
Ashutosh K.
Ex banker, Now self-employed, MD &CEO of Kumar Group of companies, Author of many books.
A TO Z ABOUT OPERATING SYSTEM: FROM ITS?GENESIS
The creation of the OS ?system requires a thousand lines of code. Their development is?using the programming languages such as C, C#, C++, and assembly language programming. Through OS we can navigate through a computer while creating the storage and executing commands. But it is not easy as it requires in-depth knowledge of Computer science and Information Technology field. Besides, the expertise to write software program which is very complex.
Therefore, we try to know about OS.
?Based on the origin to present day advancement, we may segregate generations of Operating System as under:
1. The First Generation (1940 to early 1950s)
2. The Second Generation (1955 - 1965)
3. The Third Generation (1965 - 1980)
4. The Fourth Generation (1980 - Present Day)
WHAT IS OS?
The OSs act as an intermediary between programs and the computer hardware functions, such as input and output and memory allocation, although the application code is generally affected directly by the hardware. Operating systems are created on any type of computing device, like,?a smartphone, Ipad, Ipod, web servers, video game console, web servers, laptop, supercomputer, etc. ?Thus, it manages computer hardware and provides the resources that applications need to run. Writing an OS from scratch requires a strong command of computer science, a programming language like C or C++, assembly, and code management practices. OSs serve as the underlying platforms which connect computer hardware and software. They provide users with a graphical interface (GUI) through which they issue commands and perform tasks on electronic devices. Billions of people?make use of these devices and their OSs on a regular basis, meaning that the companies that develop these widely used technologies have a great deal of influence on the daily lives of internet users around the world. Although Microsoft Windows is the clear leader in terms of desktop OSs, the company’s mobile device OS failed to make a successful transition into the smartphone market, where?Android and iOS are only two alternatives. Linux-based OS is the lightest and fastest OS in the market right now. It doesn’t need a powerful processor unlike Windows to operate at an optimal level. Linux-based OS like Ubuntu Server, CentOS server, Fedora is great options especially for running business enterprises where substantial computing power is mandatory.
PC DOS was an early personal computer OS that featured a command-line interface. The leading general-purpose personal?computer?operating system is?Microsoft Windows?having a market share of around 76 %.?followed by macOS?by?Apple Inc. with 18% share, and along with all variants of Linux with 2%.?In the?mobile?sector (including smartphones and?tablets),?Androids?share is?72% in 2020 and iOS merely above 10%., rest of the OSs are less than 1%. Linux distributions?enjoy a prime position in the server and supercomputing sectors. Other specialized classes of operating systems (specific use operating systems),?such as?embedded security?and real-time systems, Security-focused operating system?also have to be for several applications. Some operating systems have low system requirements (e.g.?Lightweight Linux distribution.). Others may have higher system requirements. Some operating systems require installation or may come pre-installed with purchased computers (OEM-installation), whereas others may run directly from media (i.e.?Live CD) or flash memory (i.e. USB?stick).?
Advantages of Operating System
The disadvantage of the Operating System
?TYPES OF OSs BASED ON PERFORMANCE
These OSs are as under :
?SINGLE-TASKING AND MULTI-TASKING
A single-tasking OS can only run one program USB at a time, while a?multi-tasking?operating system allows more than one program simultaneously with the help of time-sharing which enables available processor time to be divided between multiple processes as each broken up constantly in?time slices?by a task-scheduling subsystem of the operating system. Multi-tasking may be categorized in preventative and collaborative natures which help the operating system slice by allowing the?CPU?time and commits a slot to each one of the programs whereas Unix-like Oss like Linux and non-Unix-like, such as AmigaOS?backing preventative multitasking. Collaborative multitasking is attained by trusting each process to deliver time to the other processes in a well-defined manner.?16-bit ?versions of Microsoft Windows deployed cooperative multi-tasking;?32-bit?versions of both Windows NT and Win9x employed preemptive multi-tasking.
?SINGLE- AND MULTI-USER
Single-user OS has no means to differentiate users and permit?multiple programs to conform with the rules.?A?multi-user OS enlarges the primary concept of multi-tasking to facilitate finding processes and resources, attaching to multiple users, and the system authorizes multiple users to interrelate with the system concurrently. Time-sharing OSs plan jobs to use the system effectively comprising processing to keep financial accounts software for pricing provision of processor time, mass storage, printing, and other possessions to multiple users.
?DISTRIBUTED & TEMPLATED
A?distributed (divided amongst the constituent computers) OS?controls a group of discrete, networked computers,?and brands them to look like a single computer, as all computations are distributed.??In the background of distributed and?cloud computing?OS,?templating?denotes collecting a single virtual?machine's image?as an invitee OS which works as a tool for multiple running?virtual machines.?The system is used both in?virtualization?and cloud computing administration and is well shared in huge server warehouses.
?EMBEDDED & REAL-TIME
Embedded OSs?are planned in detail rules to be applied?in?embedded computer systems. They are drawn to work on small machines with less autonomy (e.g.?PDAs). They are very solid and the most efficient by outline, and are able to operate with even inadequate amount of resources, like?Windows CE, Minix?3.
A?real-time OS ?promises to process?events?or data at a specific moment in time. Though the said OS enabled for use of both single- or multi-tasking, when multitasking applies specialized scheduling algorithms, following or relating to the philosophical doctrine of determinism, which holds that all facts and events are determined by external causes and follow natural laws and that there is no free will. This is an event-driven system shift between jobs based on their priorities or external events, on the contrary, the time-sharing OSs allow or stop jobs based on clock interrupts. An?interrupt?(also known as a trap)?is a request for the processor?to?interrupt?currently executing code (when permitted) so that the event can be processed in a timely manner. If the request is accepted, the processor will suspend its current activities, save its state, and execute a?function?called an?interrupt handler?(or an?interrupt service routine, ISR) to deal with the event. This interruption is often temporary, allowing the software to resume normal activities after the interrupt handler finishes, although the interrupt could instead indicate a fatal error. Interrupts are generally used by hardware devices to point to electronic or physical state changes that require time-sensitive attention. It is also usually provided to implement?computer multitasking, especially in?real-time computing. Systems that use interrupts in these ways are said to be interrupted-
?LIBRARY
A library OS is providing the services that a typical operating system provides, like networking, is on the condition that in the form of?libraries?and self-controlled with the application and configuration code to paradigm a?uni-kernel: a specialized,?single address space, machine image that can be deployed to the cloud or embedded environments.
HISTORY OF OPERATING SYSTEM(OS)
Early computers were working as a calculator used for a series of single tasks. ?Basic OS attributes were advanced in the 1950s, such as resident monitor tasks that could automatically run diverse programs in the string to fast processing. But modern and highly complex structure OSs emerged in the early 1960s.?Hardware forms were denoting an increased or enhancing quality or factor. This enabled use of?runtime libraries interrupts, and parallel processing. With the passage of time, personal computers expanded widespread or made common in the 1980s, OSs were completed having a similar concept being used on larger computers. The earliest electronic digital systems in 1940 ?had no OSs. EDSA was automated on rows of mechanical switches or by jumper wires on?plugboards. These special-purpose systems comprised, generated ballistics tables for the military or controlled the printing of payroll checks from data on punched paper cards. Later programmable general-purpose computers were invented,?machine languages (consisting of strings of the binary digits 0 and 1 on punched paper tape) were introduced that sped up the programming process (Stern, 1981). OS/360?was used on most?IBM?mainframe computers starting in 1966, including computers used by the Apollo Program. By the 1950s, a computer could apply for only one program at a time. Each user had sole use of the computer for a limited period and would arrive at a scheduled time with their program and data on punched paper cards or?punched tape.
The program would be loaded into the machine, and the machine would bung machine Universal?Turing Machine. Subsequently, machines emerged libraries of programs capable of linking a user's program to help in operations such as I/O and?assembling?(creating machine code from human-readable?symbolic code).
THE GENESIS OF THE MODERN-DAY OS
The genesis of the modern-day OS began from the above developments. But, machines still performed a single job at a time. The advent of Manchester Atlas?in 1962, paved the way for?advanced Atlas Supervisor which is to be considered by many as the first recognizable modern operating system. Brinch Hansen?pronounced it as "the most significant breakthrough in the history of OSs.??
?HISTORY OF MAINFRAMES
At their core,?mainframes?are high-performance computers with large amounts of memory and processors that process billions of simple calculations and transactions in real-time. The mainframe is critical to commercial databases, transaction servers, and applications that require high resiliency, security, and agility.?
During the 1950s, several important attributes were pioneered in OSs on?mainframe computers, including?batch processing, I/O, interrupting, buffering, multitasking, spooling, runtime libraries, link-in loading, and programs for sorting?records in files. These distinctive attributes were included or not included in application software at the option of application programmers, rather than in a separate OS used by all applications. In 1959, the?Share OS?was released as an integrated utility for the?IBM 704, and later in the 709,?and?7090?mainframes, although it was quickly supplanted by IBSYS/IBJOB on the 709, 7090, and 7094. During the 1960s, IBM's?OS/360?propounded the concept of a single OS across an entire product line, which was decisive for the success of the System/360 machines. IBM's current mainframe operating systems are?distant descendants?of this original system and modern machines are?backward compatible?with applications written for OS/360 which also made the concept that the OS preserves trail of all of the system resources that are used, including program and data space allocation in main memory and file space in secondary storage, and?file locking?during the process of up-dating. If a process is stopped for any reason, all of these resources are recovered by the OS.
The substitute?CP-67?system for the?S/360-67?initiated a complete whole line of IBM OSs intensive on the concept of virtual machines. Rest ?OSs used on IBM S/360 series mainframes included systems developed by IBM:?DOS/360?(Disk Operating System),?TSS/360?(Time-Sharing System),?TOS/360?(Tape Operating System),?BOS/360?(Basic Operating System), and ACP?(Airline Control Program), as well as a few non-IBM systems:?MTS?(Michigan Terminal System), Music?(Multi-User System for Interactive Computing), and?Orval?(Stanford Timesharing System). Control Data Corporation?developed the SCOPE OSs in the 1960s, for?batch processing. In collaboration with the University of Minnesota, the Krono?and later the NOSNOS?operating systems were developed during the 1970s, which supported simultaneous batch and timesharing use. Like many commercial timesharing systems, its interface was an extension of the Dartmouth?BASIC OSs, one of the pioneering efforts in timesharing and programming languages. In the late 1970s, Control Data and the University of Illinois developed the PLATO?OS, which used plasma panel displays and long-distance time-sharing networks. Plato was remarkably innovative for its time, featuring real-time chat, and multi-user graphical games.
In 1961,?Burroughs Corporation?developed B5000?with the?MCP?(Master Control Program) operating system. The B5000 was a?stack machine?designed to wholly support high-level languages with no assembler;?indeed, the MCP was the first OS to be written exclusively in a high-level language (ESPOL), a dialect of?ALGOL). MCP also introduced many other ground-breaking innovations, such as being the first commercial implementation of?virtual memory. During the development of the?AS/400, IBM made an approach to Burroughs to license MCP to run on the AS/400 hardware. This proposal was declined by Burroughs management to protect its existing hardware production. MCP is still in use today. ?Unisys?company's?MCP/Clear Path Clear PMCP/?line of UNIVA Computers. UNIVAC, the first commercial computer manufacturer, produced a series of EXEC operating systems. Like all early main-frame systems, this batch-oriented system managed magnetic drums, disks, card readers, and line printers. In the 1970s, UNIVAC produced the Real-Time Basic (RTB) system to support large-scale time sharing, also patterned after the Dartmouth BC system. General Electric and MIT?developed General Electric Comprehensive Operating Supervisor (GECOS), which introduced the concept of ringed security privilege levels. After acquisition by Honeywell,?it was renamed?General Comprehensive OS.?(GCOS).
Digital Equipment Corporation developed many OSs for its various computer lines, including?TOP-10,?and?TOPS-20?time sharing systems for the 36-bit PDP-10 class systems. Before the widespread use of UNIX, TOPS-10 was a particularly popular system in universities, and in the early ARPANET?community.RT-11?was a single-user real-time OS for the?PDP-11?class minicomputer, and?RSX-11?was a similarly multi-user OS.
From the late 1960s through the late 1970s, several hardware competencies advanced that permitted similar or ported software to run on more than one system. Early systems had utilized?microprogramming?to implement features on their systems in order to permit different underlying computer architecture?to appear to be the same as others in a series. In fact, most 360s after the 360/40 (except the 360/44, 360/75, 360/91, 360/95, and 360/195) were microprogrammed implementations.
The massive investment in software for these systems made since the 1960s caused most of the original computer manufacturers to continue to develop compatible OSs as well the hardware.
Notable supported mainframe operating systems include:
·???????Burroughs MCP?–?B5000, 1961 to?Unisys?Clearpath/MCP, present, IBM?OS/360?–?IBM System/360, 1966 to IBM?z/OS, present, IBM?CP-67?–?IBM System/360, 1967 to IBM?z/VM, UNIVAC?EXEC 8?–?UNIVAC 1108, 1967, to?OS 2200?Unisys?Clearpath Dorado, present
Mac OS by?Apple Computer?developed the first widespread OS to feature a graphical user interface (GUI). Many of its features such as windows and icons would later become commonplace in GUIs.
The first?microcomputers?did not have the capacity or need for the elaborate operating systems that had been developed for mainframes and minis; minimalistic operating systems were developed, often loaded from?ROM?and known as?monitors. One notable early?disk operating system(DOS)?was?CP/M, which was supported on many early microcomputers and was closely copied by?Microsoft’s MS-DOS, which turned out historical development still ruling the roost and became widely popular as the OS selected for the?IBM PC?(IBM's version of it was called IBM DOS or?PX DOS). Apple Computer Inc. (now?Apple Inc.) in 1981 cast off its popular Apple-II?series of microcomputers to present the?Apple Macintosh?computer with a novel (GUI) to the Mac OS.
The overview of the?Intel 80386?CPU chip in October 1985,?with32-bit?architecture and?paging?capabilities, provided personal computers with the ability to operate?Multi-tasking OS as earlier minicomputers and?mainframes. Microsoft answered to this progress by hiring?Dave Cutler, who had developed the?VMSOS for?Digital Equipment Corporation. He would lead the development of the?Windows OS, which remains to serve as the basis for Microsoft's operating systems line. Steve Jobs, a co-founder of?Apple Inc., started?NeXT?Computer Inc., which developed the?NESTSTEPOS. NEXTSTEP would later be acquired by?Apple Inc.?and used, along with code from FreeBSD as the core of?MAC OSX?(macOS after the latest name change).
The?GNU Project?was started by activist and programmer?Richard Stallman?with the goal of creating completely?free software as a?replacement to the proprietary?UNIX OS. While the project was extremely effective in duplicating the functionality of various parts of UNIX, the development of the?GNU Hurd?kernel proved to be unproductive. In 1991, Finnish computer science student Linus?Torvalds, with cooperation from volunteers collaborating over the Internet, released the first version of the?Linux kernel. It was soon merged with the GNU?userspace?components and?system software?to form a complete OS. Since then, the combination of the two major components has usually been referred to as simply "Linux" by the software industry, a naming convention that Stallman and the?Free Software Foundation?remain opposed to, preferring the name GNU/Linux. The Berkeley Software Distribution, known as?BSD, is the UNIX derivative distributed by the University of California, Berkeley, starting in the 1970s. Freely distributed and?ported?to many minicomputers, it eventually also gained a following for use on PCs, mainly as?FreeBSD, NetBSD, and OpenBSD.
?UNIX AND UNIX-LIKE OPERATING SYSTEMS
?Unix was initially written in?assembly language.?Ken Thompson?wrote?B, mainly based on BCPL, based on his experience in the?MULTICS?project. B was replaced by?C, and Unix, rewritten in C, developed into a large, complex family of inter-related operating systems which have been influential in every modern operating system. A?Unix-like?family is a diverse group of OSs, with several major sub-categories including?BSD, System V, and?Linux. The name "UNIX" is a trademark of?The Open Group?which licenses it for use with any operating system that has been shown to conform to their definitions. "UNIX-like" is commonly used to refer to the large set of operating systems that resemble the original UNIX. Unix-like systems operate on an extensive variety of?computer architecture. They are used heavily for servers?in business and like workstations?in academic and engineering environments.?Free?UNIX variants, such as Linux?and?BSD, are popular in these areas.
Five OSs are certified by?The Open Group?(holder of the Unix trademark) as Unix. HP's?HP-UX?and IBM's?AIX?are both descendants of the original System V Unix and are designed to run only on their respective vendor's hardware. In total dissimilarity,?Sun Microsystems'?Solaris?can be operated on multiple types of hardware, includingx86,?Sparc?servers, and PCs. Apple's?macOS, a replacement for Apple's earlier (non-Unix) Mac OS, is a hybrid kernel-based BSD variant derived from NeXTSTEP,?Mach, and?FreeBSD. IBM's?z/OS UNIX System Services?includes a shell and utilities based on?Notice?Inter Open products. Unix interoperability was pursued by launching the?POSIX?standard. The POSIX standard can be applied to any OS, whereas it was originally created for various Unix variants.
?Berkeley Software Distribution(BSD) and its descendants
The first server?for the?World Wide Wave(WWW)?ran on NeXTSTEP, based on BSD. A subgroup of the Unix family is the?BSD ?family, which includes?FreeBSD, NetBSD, ?and?OpenBSD. These operating systems are most commonly found on?webservers, although they can also function as a personal computer OS. The Internet owes much of its existence to BSD, as many of the protocols now commonly used by computers to connect, send and receive data over a network were widely implemented and refined in BSD. The?WWW?was also first demonstrated on a number of computers running an OS based on BSD called?NeXTSTEP.
In 1974,?the University of California Berkeley?adopted its first Unix system. Over time, students and staff in the computer science department there began adding new programs to make things easier, such as text editors. When Berkeley received new?VAX?computers in 1978 with Unix installed, the school's undergraduates modified Unix even more in order to take advantage of the computer's hardware possibilities. The Defense Advanced Research Projects Agency?of the US?Department of Defense?acquired interest and pronounced to fund the project. Many schools, corporations, and government organizations took notice and started to use Berkeley's version of Unix instead of the official one distributed by AT&T.Steve Jobs, upon leaving Apple Inc. in 1985, formed?NeXT Inc., a company that manufactured high-end computers running on a variation of BSD called?NeXTSTEP. One of these computers was used by Tim Berners-Lee as the first webserver to create the WWW.
Developers like?Keith Bostic?invigorated the project to change any non-free code that was initiated with Bell Labs. Once this was done, however, AT&T sued. After two years of legal disputes, the BSD project produced a number of free derivatives, such as NetBSD?and?FreeBSD?(both in 1993), and?OpenBSD?(from NetBSD in 1995).
THE IMPORTANCE OF macOS
macOS?(formerly "Mac OS X" and later "OS X") is a line of open core?graphical OSs developed, marketed, and sold by Apple Inc.,? the latest of which is pre-loaded on all currently shipping?Macintosh?computers. macOS is the successor to the original?classic Mac OS, which had been Apple's primary operating system since 1984. Unlike its predecessor, macOS is a?UNIX OS ?built on technology that had been developed at?NeXT?through the second half of the 1980s and up until Apple purchased the company in early 1997. The operating system was first released in 1999 as Mac OS X Server 1.0, followed in March 2001 by a client version (Mac OS X v10,0 Cheetah) since then, six more distinct "client" and "server " editions of macOS have been released, until the two were merged in?OS X 10.7 Lion.
Prior to its merging with macOS, the server edition?–?macOS Server was?structured?identical to its desktop counterpart and usually ran on Apple's line of Macintosh?server?hardware. macOS Server included workgroup management and administration software tools that provide simplified access to key?networks services, including a?mail transfer agent, a?Samba server, an?LDAP?server, a domain name server, and others. With?macOS Xv10.7 Lion, all server aspects of Mac OS X Server have been integrated into the client version, and the product re-branded as "OS X" (dropping "Mac" from the name). The server tools are now offered as an application.
?Z/OS UNIX SYSTEM SERVICES: LINUX AND LINUX KERNEL???
First introduced as the OpenEdition upgrade to?VMS/ESA?System Product Version 4 Release 3, announced?February 1993 with support for?POSIX?and other standards.[18][19][20],?z/OS?UNIX System Services?is built on top of?VMS?services and cannot run independently. While IBM initially introduced OpenEdition to satisfy?FIPS?requirements, several z/OS components now require UNIX services, e.g., TCP/IP.
?Linux, a?Unix-like OS?was first time released on September 17, 1991, by Linus Torvalds and?Picture of?Tux?the?penguin, mascot of Linux. The Linux kernel originated in 1991, as a project of Linus Torvalds while a university student in Finland. He posted information about his project on a newsgroup for computer students and programmers and received support and assistance from volunteers who succeeded in creating a complete and functional kernel.
Linux?is?Unix-like but was advanced without any Unix code, unlike BSD and its variants. Because of its open license model, the?Linux kernel?code is available for study and modification, which resulted in its use on a wide range of computing machinery from supercomputers to smart-watches. Although estimates suggest that Linux is?used on?only 1.82% of all "desktop" (or laptop) PCs,?it has been widely adopted for use in servers, and embedded systems, such as cell phones. Linux has superseded Unix on many platforms and is used on most supercomputers including the top 385.?Many of the same computers are also on?Green500?(but in a different order), and Linux runs on the top 10. Linux is also commonly used on other small energy-efficient computers, such as?smartphones?and?smartwatches. The Linux kernel is used in some popular distributions, such as?Red Hat,?Debian,?Ubuntu,?Linux?and?Google’s Android,?Chrome OS, and?Chromium OS.
?THE MOST POWERFUL AND WIDELY USED GLOBALLY MICROSOFT WINDOWS(MWs)
Windows is an unstructured OS having restricted open-source, building the state of being functional on to Windows is a quite hard job. While Android can be said to be a variant of Linux, a structured and open-source OS. Though it allows adding functionality layers is easy, too many layers result in a bad user experience. It would undoubtedly necessitate having wide-ranging knowledge of Android?and insider knowledge of how some core components of Windows work. ?
?Microsoft Windows is a family of?proprietary OS delineated by?Microsoft Corporation?and primarily targeted to Intel-style-based computers, with an estimated 88.9 percent total usage share on web-connected computers.?The latest version is?Window 11.
Windows 7 overtook Windows XP as the most common version in use in 2021. MWs was first released in 1985, as an?operating environment?running on top of?MS-DOS, which was the standard OS shipped on most Intel architecture personal computers at the time. In 1995,?Windows 95?was released which only used MS-DOS as a bootstrap. Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS- and JavaScript-based design templates for typography.
For backward compatibility, Win9x could run real-mode MS-DOS?and 16-bit?Windows 3. x?drivers.?Windows ME, released in 2000, was the last version in the Win9x family. Later versions have all been based on the?Windows NT kernel. Current client versions of Windows run onIA-32,?x86-84,?and ARM?microprocessors.?In addition,?Itanium?is still supported in the older server version of Windows Server 2008 R2. In the past, Windows NT supported additional architectures. Server editions of Windows are widely used. In recent years, Microsoft has expended significant capital in an effort to promote the use of Windows as a?server OS. However, Windows' usage on servers is not as widespread as on personal computers as Windows competes against Linux and BSD for server market share. ReactOS?is a Windows-alternative operating system, which is being developed on the principles of Windows?– without using any of Microsoft's code.
Other
There have been many OSs ?that were significant in their day but are no longer so, such as?AmigaOS;?OS/2?from IBM and Microsoft; classic Mac OS, the non-Unix precursor to Apple's macOS;?BeOS;?
XTS-300;?RISCOS;?MorphOS;?Haiku,?Baremetal,?and?FreeMind. Some are still used in niche markets and continue to be developed as minority platforms for enthusiast communities and specialist applications.?OpenVMS, formerly from?DEC, is still under active development by VMS Software Inc. Yet other OSs are used almost exclusively in academia, for OSs education or to do research on operating system concepts. A typical example of a system that fulfills both roles is MINIX, while for example?Singularity?is used purely for research. Another example is the?Oberon System?designed at?ETH Zurich?by Niklaus Wirth, Jurg Gutknecht,?and a group of students at the former Computer Systems Institute in the 1980s. It was used mainly for research, teaching, and daily work in Wirth's group. Other OSs have failed to win significant market share, but have introduced innovations that have influenced mainstream operating systems, not least Bell Labs'?Plan 9.
?COMPONENTS OF OPERATING SYSTEM
?The components of an operating system are essential as its presence assists to perform the multiple parts of computer work in tandem. All user software needs to go through the operating system in order to use any of the hardware, whether it be as simple as a mouse or keyboard or as complex as an Internet component.
OS delivers an interface between an application program and the computer hardware so that an application program can interact with the hardware only by following pre-defined rules and procedures programmed into it. This is also a set of services that simplify the advancement and implementation of application programs. Performing an application program comprises the creation of a process by the OS kernel?which assigns memory space and other resources, establishes a priority for the process in multi-tasking systems, loads program binary code into memory, and initiates execution of the application program which then interacts with the user and with hardware devices.
KERNEL
kernel joints the application software to the hardware of a computer. It requires the?firmware?and device drivers to enable the most basic level of control over all of the computer's hardware devices. It manages memory access for programs in hardware resources, it sets up or resets the CPU's operating states for optimal operation always. It also categorizes the data for long-term?non-volatile storage?with?files systems?on such media as disks, tapes, flash memory, etc.
?INTERRUPTS
These are crucial to most?OSs, as they make possible an efficient way to react to the environment. Interrupts make the?CPU have a?control flow?altered from the currently running?process.?(I/O) devices?are slower than the CPU's?clock signal. So, decelerating the computer if the CPU had to wait for each I/O to complete. Instead, a computer may implement direct memory access (DMA) I/O. The specifics of how a computer progressions an interrupt alter from architecture to architecture, and the facts of how to interrupt service sequences?from OS to OS. The situation below is typical, although the details for some other?hard wares and OSs change meaningfully.
If a?computer program?in a computer with a direct memory access chip?executes a system call?to perform a DMA I/O blocking write operation, then the system call might execute the following instructions:
1. Set the contents of the CPU's registers (including the?program counter into the?process control block. ?
2.?Generate an entry in the device-status table.?The OS arranges this table to keep track of which processes are waiting for which devices. One field in the table is the?memory address?of the process control block.?
3.??Place all the characters to be sent to the device into a?memory buffer. Set the memory address of the memory buffer to a predefined device register. Set the buffer size (an integer) to another predetermined register. Implement the machine instruction?to start the writing. Work a?context switch?to the next process in the?ready queue. While the writing completes, the operating system will context switch to other processes as normal.
?When the device finishes writing, the device will?interrupt?the currently running process by?asserting?an?interrupt request. The device will also place an integer onto the device's?data bus.?Upon accepting the interrupt request, the CPU will: Push the contents of its program counter and?program status word?onto the?call stack. Read the integer from the data bus. The integer is an offset to the interrupt vector table. The vector table's instructions will return control to the OS.
The operating system will then:?Access the device-status table. Extract the process control block. Perform a context switch back to the writing process. When the writing process has its time slice over, the CPU will: Pop from the call stack the program status word and set it back to its register. Pop from the call stack the address of the interrupted process' next instruction and set it back into the program counter. The interrupted process will then resume its time slice.
USER MODES AND SUPERVISOR MODE
Privilege rings for the?x86?microprocessor architecture are available in?protected mode. OSs decide which processes run in each mode.
Modern computers support multiple modes of operation. CPUs with this capability offer at least two modes:?user mode?and supervisor mode. Supervisor mode operation allows unrestricted access to all machine resources, including all MPU instructions. User mode operation sets limits on instruction use and typically disallows direct access to machine resources. CPUs might have other modes similar to user mode as well, such as the virtual modes in order to emulate older processor types, such as 16-bit processors on a 32-bit one, or 32-bit processors on a 64-bit?one.
At power-on or reset, the system starts in supervisor mode. Once an operating system?kernel?has been loaded and started, the boundary between user mode and supervisor mode (also known as kernel mode) is discerned.
The software interrupt causes the processor to switch from user mode to supervisor mode and begin executing code that allows the kernel to take control. The term "user mode resource" generally refers to one or more CPU registers, which contain information that the running program isn't allowed to alter. Attempts to alter these resources generally cause a switch to supervisor mode, where the operating system can deal with the illegal operation the program was attempting, for example, by forcibly terminating ("killing") the program.
MEMORY MANAGEMENT
Cooperative memory management, used by many early operating systems, assumes that all programs make voluntary use of the?kernel's memory manager, and do not exceed their allocated memory. This system of memory management is almost never seen any more, since programs often contain bugs that can cause them to exceed their allocated memory. If a program fails, it may cause memory used by one or more other programs to be affected or overwritten. Malicious programs or viruses may purposefully alter another program's memory or may affect the operation of the operating system itself. With cooperative memory management, it takes only one misbehaved program to crash the system. Memory protection enables the kernel to restrict a process' access to the computer's memory. Various methods of memory protection exist, including?memory segmentation and paging. All methods require some level of hardware support (such as the?80286?MMU), which doesn't exist in all computers.
?VIRTUAL MEMORY
?Many operating systems can "trick" programs into using memory scattered around the hard disk and RAM as if it is one continuous chunk of memory, called virtual memory.
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Latest OSs, memory which is accessed less frequently can be temporarily stored on disk or other media to make that space available for use by other programs. This is called swapping, as an area of memory can be used by multiple programs, and what that memory area contains can be swapped or exchanged on demand. "Virtual memory" provides the programmer or the user with the perception that there is a much larger amount of RAM in the computer than is really there.
?Multitasking?refers to the running of multiple independent computer programs on the same computer; giving the appearance that it is performing the tasks at the same time. Since most computers can do at most one or two things at one time, this is generally done via time-sharing, which means that each program uses a share of the computer's time to execute.
DISK ACCESS AND FILE SYSTEMS
?File systems allow users and programs to organize and sort files on a computer, often through the use of directories (or "folders").
Access to data stored on disks is a central feature of all OSs. Computers store data on?disks using files, which are structured in specific ways in order to allow for faster access, higher reliability, and to make better use of the drive's available space. The specific way in which files are stored on a disk is called a?file system and enables files to have names and attributes. It also allows them to be stored in a hierarchy of directories or folders arranged in a?directory tree.
?DEVICE DRIVERS
?These are specific types of computer software developed to allow interaction with hardware devices. Typically this constitutes an interface for communicating with the device, through the specific computer bus or communications subsystem that the hardware is connected to, providing commands to and/or receiving data from the device, and on the other end, the requisite interfaces to the operating system and software applications. It is a specialized hardware-dependent computer program that is also operating system specific that enables another program, typically an operating system or applications software package or computer program running under the operating system kernel, to interact transparently with a hardware device, and usually provides the requisite interrupt handling necessary for any necessary asynchronous time-dependent hardware interfacing needs.
NETWORKING
?Currently, most OSs assist a variety of networking protocols, hardware, and applications for using them. This means that computers running dissimilar operating systems can participate in a common network?for sharing resources such as?computing, files, printers, and scanners using either wired or wireless connections. Networks can essentially allow a computer's operating system to access the resources of a remote computer to support the same functions as it could if those resources were connected directly to the local computer.
?Client/server networking allows a program on a computer, called a client, to connect via a network to another computer, called a server. Servers offer (or host) various services to other network computers and users. These services are usually provided through ports or numbered access points beyond the server's?IP address. Each port number is usually associated with a maximum of one running program, which is responsible for handling requests to that port. A daemon, being a user program, can in turn access the local hardware resources of that computer by passing requests to the operating system kernel.
?SECURITY
?A modern OS provides access to a number of resources, which are available to software running on the system, and to external devices like networks via the kernel. TheOS must be capable of distinguishing between requests which should be allowed to be processed, and others that should not be processed. While some systems may simply distinguish between "privileged" and "non-privileged", systems commonly have a form of requester?identity, such as a user name. To establish identity there may be a process of?authentication. Often a username must be quoted, and each username may have a password. Other methods of authentication, such as magnetic cards or biometric data, might be used instead. In some cases, especially connections from the network, resources may be accessed with no authentication at all (such as reading files over a network share). Network services include offerings such as file sharing, print services, email, websites, and?(FTP), most of which can have compromised security. At the front line of security are hardware devices known as?firewalls?or intrusion detection/prevention systems. At the operating system level, there are a number of software firewalls available, as well as intrusion detection/prevention systems. Most modern operating systems include a software firewall, which is enabled by default. A software firewall can be configured to allow or deny network traffic to or from a service or application running on the operating system. Therefore, one can install and be running an insecure service, such as Telnet or FTP, and not have to be threatened by a security breach because the firewall would deny all traffic trying to connect to the service on that port.
?USER INTERFACE
?The current command prompt is at the bottom. Every computer that is to be operated by an individual requires a?user interface. The user interface is usually referred to as a?shell?and is essential if human interaction is to be supported. The user interface views the?directory structure?and requests services from the OS.
GRAPHICAL USER INTERFACES
?Most of the modern computer systems support??(GUI), and often include them. In some computer systems, such as the original implementation of the?classic Mac OS, the GUI is integrated into the?kernel. While technically a graphical user interface is not an OS service, incorporating support for one into the operating system kernel can allow the GUI to be more responsive by reducing the number of context switches required for the GUI to perform its output functions. Other OSs are?modular, separating the graphics subsystem from the kernel and the OS. In the 1980s UNIX, VMS, and many others had OSs that were built this way. Linux and macOS are aso built this way. Modern releases of Microsoft Windows such as?Windows Vista?implement a graphics subsystem that is mostly in user-space; however, the graphics drawing routines of versions between?Windows NT?and Windows Server 2003?exist mostly in kernel space.?Windows9x?had a very little distinction between the interface and the kernel.
Graphical user interfaces evolve over time. For example, Windows has modified its user interface almost every time a new major version of Windows is released, and the Mac?OS GUI changed dramatically with the introduction of Mac?OS?X in 1999.
DIVERSITY OF OPERATING SYSTEMS AND PORTABILITY
Application software is commonly ?written for use on a specific operating system, and even for specific hardware.]When porting the application to run on another OS, the functionality required by that application may be implemented differently by that OS (the names of functions, the meaning of arguments, etc.) requiring the application to be adapted, changed, or otherwise?maintained.
Unix was the first operating system not written in assembly language, making it very?portable?to systems different from its native PHP-11. This cost in supporting OSs multiplicity can be avoided by instead writing applications against?software platforms?such as?Java?or?Qt. These abstractions have already borne the cost of adaptation to specific operating systems and their?systems libraries. Another approach is for OS vendors to adopt standards. For example,?POSIX?and OS?abstraction layers?give similarities that cut porting costs.
Bill Gates (1955- ) and Paul Allen (1953- ) founded Microsoft Corporation. Microsoft was soon taking over the PC market, and some of its practices were drawing criticism. In 1997 Microsoft was ordered to make Windows 95 available without the applications software Internet Explorer. The argument was that by automatically including Internet Explorer on Windows 95, Microsoft was using its monopoly of the PC operating system market to destroy competition in other markets, such as internet software. Microsoft appealed the order. An appeal court ruled that the 1995 injunction did not apply to Windows 98, released in 1998. However, in May of that same year, the U.S. Justice Department and 20 states filed an antitrust suit against Microsoft, charging it with abusing its market powers to destroy competitors. In November 1999 Judge Thomas Jackson issued his Findings of Fact, stating that Microsoft is an illegal monopoly and that it had abused its market power in anti-competitive practices.
THE EMERGENCE OF LINUX
While Apple and Microsoft were battling for space in the PC market, Linus Torvalds (1970- ) at the University of Helsinki in Finland was developing a freely distributed version of UNIX for personal computers called Linux. Linux began as a hobby for Torvalds, inspired by Minix, a small UNIX system developed by Andy Tanenbaum. In October 1991 Torvalds announced the first official version of Linux, 0.02. The system was still very rudimentary, but Torvalds put it out on?the internet?for UNIX programmers and wizards to aid in its development. Hackers, programmers, and users of every flavor contributed, and by 1994 it had become a viable operating system, capable of running almost all UNIX programs. By 1996 Linux was a complete UNIX clone, capable of running X-windows—the UNIX version of a GUI. Because Linux was developed completely from scratch, it contains no code from AT&T or any other proprietary source. Much of the software available for Linux is from the GNU Project at the Free Software Foundation in Cambridge, MA. In 1999 it was still possible to obtain Linux and a sizeable number of programs completely free of charge. Because of its flexibility, its price, and the fact that it is adaptable to most PC hardware, Linux became quite popular in the late 1990s as an Internet server. The growing interest in Linux convinced commercial software manufacturers to make their packages compatible with the Linux system. As this trend continues Linux will become even more viable and popular.
?IMPACT
The pace of change in the computer industry makes it impossible to predict future developments in operating systems. However, this article has attempted to show that the evolution of operating systems in the second half of the twentieth century depended on a number of factors, including programmer interest, market pressures, hardware advances, and government oversight. Operating systems will continue to develop to meet the growing and changing needs of users and new hardware. It can only be hoped that the competition that gave rise to the PC revolution, the innovation that brought about GUI systems, and the free exchange of ideas that gave rise to Linux will all continue into the twenty-first century.
The first operating system used for real work was GM-NAA I/O, produced in 1956 by?General Motors’ Research division?for its IBM 704. Most other early operating systems for IBM mainframes were also produced by customers.
?Who is the founder of the operating system?
The inventor of Disk Operating System(DOS)?Gary Kildall. DOS went on to transform into OSs that we all use today. Before his invention, every computer chip needed to have its own set of codes for users to interact with the computer.
Is Oracle an operating system?
An?open and complete operating environment, Oracle Linux delivers virtualization, management, and cloud-native computing tools, along with the operating system, in a single support offering. Oracle Linux is 100% application binary compatible with
Is Intel an operating system?
Buried deep inside your computer’s Intel chip is?the MINIX operating system?and a software stack, which includes networking and a web server. It’s slow, hard to get at, and insecure as insecure can be.
GUI (Graphical User Interface) A graphics-based operating system interface that uses icons, menus, and a mouse (to click on the icon or pull down the menus) to manage interaction with the system. Developed by Xerox, the GUI was popularized by the Apple Macintosh in the 1980s.
In 1968, when 13-year-old Bill Gates was still programming tic-tac-toe in BASIC, an engineer named Douglas Englebart at the Stanford Research Institute introduced the world to the mouse
The latest version of Ubuntu is 18 and runs Linux 5.0, and has no obvious performance weaknesses. The?kernel operations?seem to be the fastest across all operating systems. The graphical interface is roughly on par or faster than other systems.
?Top 10 Most Secure Operating Systems
1. OpenBSD. By default, this is the most secure general-purpose operating system out there. …
2. Linux. Linux is a superior operating system. …
3. Mac OS X. …
4. Windows Server 2008. …
5. Windows Server 2000. …
6. Windows 8. …
7. Windows Server 2003. …
8. Windows XP.
?Obnox OS: The Worst Operating System
Kildall, a Seattle native 1972 graduate of the University of Washington,?was?the creator?of the landmark personal computer operating system CP/M,?playing a critical?role in the PC revolution. He will be?recognized posthumously for that contribution, in addition to his invention of BIOS, with a rare IEEE Milestone plaque being unveiled this morning — joining?the technology?industry’s equivalent of the Hollywood Walk of Fame.
Kildall, who passed away in 1994 at the age of 52, has been called the “man who could have been Bill Gates,” thanks to a Global market share held by computer operating systems 2012-2021, by mont Published by?Statista Research Department,?Feb 23, 2022
?Microsoft’s Windows is the most widely used computer operating system in the world, accounting for 69.61 percent share of the desktop, tablet, and console OS market in December 2021. Apple’s macOS and iOS rank as the next most widely used operating systems, with the latter being the standard installation on all iPad devices. Linux OS versions serve as the primary option for users who prefer open-source software and intend to avoid the influence of major OS developers.
LIST OF 10 ?THE TOP?MOST POPULAR OPERATING SYSTEMS WITH FEATURES AND COMPARISON.
?The cyber era or virtual world has shown frequently the advent of the miracle of technology. One of these miracles that have made our lives simpler, faster, and more entertaining is the computers. Computers are a revolutionary invention that really changed the course of human civilization. It has evolved from bulky desktop boxes to more portable and convenient laptops and mobile phones.
?10 Best Operating Systems In Market
1, MICROSOFT
?Having robust User Interface which helps in easier navigation, with a start menu on the left side by listing out options and representing applications. The Task View feature lets the users switch between multiple workspaces at once, by displaying all the open Windows. Two separate user interfaces, one for mouse and keyboard, and the ‘Tablet Mode’ designed for touchscreens. Multifactor authentication technology for higher security like BIN, PIN, Fingerprint recognition, etc. Automatically compress system files to reduce the storage footprint.
?The Windows software is simply best because of how it has evolved with time. Its security system is state-of-the-art, its user interface allows convenient usage irrespective of the device that you are using it on.
It is backed by Canonical which is a global software company, and now by the leading Ubuntu service providers.
Ubuntu is an Open Source software, which allows it to be freely downloaded, used, and shared by its users. It comes with a built-in firewall and virus protection software, making it the most secure OS around. It provides five years of security patches and updates. It is fully translated into 50 different languages. It works and is compatible with all the latest laptops, desktops, and touch screen devices.?Ubuntu is a great option for those with holes for pockets. Its open-source feature is enticing enough to attract many users. But, it also makes up in quality by providing a robust interface, and security features that are too hard to pass on.
3) MAC OS.
The Mac OS has been the staple of almost all Apple devices as we can remember. It has evolved with time to include the features that first and foremost define innovation In recent years, the MAC operating systems have been completely free with the occasional free upgrade by its developers. For Apple users, there is no other option except the MAC OS.
The new dark mode gives your desktop interface a more dramatic look which is easier on the eyes. A dynamic desktop that helps to automatically organize your desktop files by kind, date, or tag. Continuity camera that scans or photographs a document nearby your iPhone and automatically appears on your mac.
Discover handpicked apps with the MAC app store. New iTunes allows users to search for songs with few lyrics. Prevent websites from tracking your Mac by making your profile more anonymous online.?Mac’s biggest accomplishment is in its dynamic appearance look and design of its interface. It is probably one of the best-looking OS today. Now, Apple is allowing its users to get their hands on this OS and all its upgrades for free.
?4) FEDORA
Fedora is another Linux-based system that gives Ubuntu’s open-source features a run for the money. Fedora is reliable, user-friendly and makes for a powerful OS for any laptop and desktop computer. Fedora is the OS that is for casual users and caters to students, hobbyists, and professionals working in corporate environments. ?Although also good for personal use, fedora works best for developers in the corporate environment. It has all the tools and utilities that a developer needs to work on in their projects and is free of cost!
5) SOLARIS
?It is the best for?Large workload processing, managing multiple databases, etc. Solaris is a UNIX-based operating system that was originally developed by Sun Microsystems in the mid-’90s. In 2010 it was renamed Oracle Solaris after Oracle acquired Sun Microsystems. It is known for its scalability and several other features that made it possible such as Dtrace, ZFS, and Time Slider.
?Provides the most advanced security features in the world such as process and user rights management, thereby allowing you to secure mission-critical data. It offers indisputable performance advantages for web, database, and java-based services. Delivers high-performance networking without any modification. Unlimited capacity for helping in managing file systems and databases. Allows seamless inter-operability for solving hundreds of hardware and software problems. Oracle Solaris is considered as one of the best free open source OS in the industry by most of them. It allows for scalability, interoperability, data management, and security which are all critical for businesses with the need for a high-end OS.
?6) FREE BSD
?It is best suited for networking, Internet, and Intranet server compatibility. FreeBSD, as the name suggests is a free UNIX-based open-source software. It is compatible with a variety of platforms and mainly focuses on features such as speed, and stability. The most fascinating part about this software is its origin. It was built at the University of California by a large community.?
Advanced networking, compatibility, and security features are still missing in many OS today. Ideal for internet and intranet services and can handle large loads and manages memory efficiently to maintain good responses for multiple simultaneous users. Advanced embedded platform catering to higher-end Intel-based appliances. Easy to install using CD-ROM, DVD, or directly over the network using FTP and NPS.?Free BSD’s biggest appeal is its ability to deliver a robust OS, given the fact that it was built by a large community of students. It is best for networking, is compatible across multiple devices, and is very simple to install.
?7) CHROME OS
An integrated media player that enables the users to play MP3s, view JPEG and handle other multimedia files while offline. Remote application access and virtual desktop access. Chrome OS is designed to be compatible with all Android applications.
With Chrome OS it is possible to run Linux applications. Chrome OS is an OS that works fine, but there is still a lot of promise to what it might eventually become. For now, it is good for multi-media, Linux, and Android applications. For the other features, we will have to just wait and watch.
?8) CENTOS
?It is the best for?Coding, Personal, and Business Use. CentOS is another community-driven open source free software that allows robust platform management. It is best for developers who are looking for an operating system that simply helps them to perform their coding tasks. That’s not to say that it has nothing to offer those who simply want to use it for mundane purposes.
?Extensive resources for coders looking to build, test, and release their codes. Advanced networking, compatibility, and security features are still missing in many OS today. It allows for seamless interoperability by solving hundreds of hardware and software problems. It provides the most advanced security features in the world such as process and user rights management, thereby allowing you to secure mission-critical data. CentOS makes their coding work simpler and faster. Moreover, it is free.
?9) DEBIAN
?It is the best for running Apps. Debian is again a Linux kernel-based free open-source OS. It comes with over 59000 packages and is a pre-compiled software bundled in a nice format. It is easy to install and offers a user-friendly interface.?Faster and lighter than the other OS, irrespective of the processor speed. It comes with in-built security firewalls to protect valuable data. Easy to install through any medium. Advanced networking, compatibility, and security features are still missing in many OS today.?Debian might not be the most versatile of the OSs, but its free open source feature makes it worthwhile.
?10) DEEPIN
?Deepin is an open-source OS based on Debian’s stable branch. It features DDE, (Deepin Desktop Environment built on QT. It has been praised for its beautiful aesthetics and very appealing interface. Simple Installation Procedure. Home to custom-tailored Deepin apps like font installer, file manager, screenshot, Deepin screen recorder, voice recorder, image and movie viewer, etc.?Deepin can very well qualify as its own little niche OS. It is free and improves upon many shortcomings of Debian. With more modifications, it will compete with the top OSs like Windows and Mac in no time.
CONCLUSION
An OS is a fuel that is required to run our computer at our convenience. There are many OS out there that make it possible. Choose the best OS that suits our needs and comfort.
The Best OS must be capable of:
????????Running critical computing applications.
·???????Manage a device’s software and hardware.
·???????Connect with the CPU for memory and storage allocation.
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