History of Computing - a collection of linked in posts from 2021

1.????Aug 2021 – The origins of the word “bug”

The word "bug" was used by Grace Hopper to describe the malfunction of the MARK II computer. Grace had used the word literally as a dead moth was found in one of the relays ( yes, early computers were electro-mechanical).

Since then, the word "bug" has been used by?#softwaredevelopers, lovingly, to refer to any malfunctioning of a computer program, whether the malfunction is due their own mistake or a mistake made by some other developer.

A software "bug" can be as lethal as a real bug in causing massive devastation- crashing planes, deaths due to overdosage of drugs , cars accelerating when brakes are pressed -- thousands of crores lost when a stock exchange software malfunctions ( the recent NSE failure for example), wrong people arrested because of flaws in facial recognition... the list is endless.

What will be the next major disaster caused by a "bug"? My own guess is that something like the failure of an Inter- bank settlement software will bring down the economy of some country to a standstill.

2.??????Aug 2021- High-level languages and early OSs

Contrary to popular opinion, FORTRAN wasn't the first high level language. The earliest proposal for a high level language came from a German computer scientist, Konrad Ruse in 1943, for a computer that he had built. The language was called Plankalkül-- but it never got implemented.

First real high level compiled language was Autocode(1951). This language was popular till the 80s, and even Indian training companies taught it till about 1985.

What about the first operating system? It wasn't the IBM OS/360. The first OS was built by General Motors Research, for the IBM computers they had bought. This was created in 1956 -- a decade before the OS/360 and was called GM-NAA IO. In fact, many of IBM's customers built their own OSs. IBM consolidated all these ideas and created a single OS for all its computers (by standardizing the hardware instruction sets and I/O as well).

The OS 360 revealed the problems of developing software at scale and was the subject of study in books such as " The Mythical Man-month". Watts Humphrey, one of the program managers, went on to set up SEI in CMU.

3.??????Sep 2021 – evolution of computers

The first electronic computer was built by Ferranti and was based on the University of Manchester Mark I.

IBM did not enter this business till a few years later when it came up with the 701. In fact they were a reluctant entrant - in 1943 Thomas Watson Sr,, famously said "I think there is a world market for maybe five computers."!!

By the 60s, however IBM dominated the Industry. And it had 6 major competitors, Burroughs, Sperry-Univac, National Cash Register (NCR), Control Data Corporation(CDC) , Honeywell. Together, they were referred to as the BUNCH, and their combined market share was less than that of IBM.

The computer Industry was called IBM and the Bunch!!

Burroughs and Sperry-Univac merged to form Unisys in 1986- NCR exited the traditional computing business, and now has most of the ATM market share and has a significant presence in the POS market. Honeywell, now, is a dominant player in the industrial automation segment. CDC left the computer business in 1988- and currently is a part of Ceridian. (Seymour Cray, the founder of supercomputing firm Cray Computers, was an ex-CDC employee.)

4.??????Sep 2021 – Unix and C

The original Unix system, which ran on PDP 7 was written in assembly language. Between the original and the 4th version of?#Unix, Dennis Ritchie ( and his formidable team) developed the C language and had implemented the kernel using the new language. However, Unix wasn't the first OS to be written (largely) in a high level language -- for example, the Multics system was written using PL/1.

Brian Kernighan and Ritchie published "The C Programming language" , in 1978- commonly known as K&R.

Stephen Johnson, of the same team, created the "portable" C compiler in 1979, which became the basis of almost all?#Clanguage?compilers of the future.

C, unlike successor C++, hasn't undergone much change since 1989, when the ANSI standards were adopted. If one had gone to sleep in 1990 and woken up in 2021, one would be able to pick up one's C code where one left off!! This isn't so for C++- A?#Cpp?Rip van Winkle would find it unrecognizable in 2021!!

Nearly 50 years after it was created by Dennis Ritchie, C, along with its successor C++,continues to be the language for building foundational infrastructure software in computers.

Ken Thompson ( one of members of Ritchie's team) along with Rob Pike and others created Go language in 2009 at google.

Dennis Ritchie passed away in 2011.

5.??????Oct 2021- Minicomputers, Cores etc

In the 50s,60s and 70s, "mainframe" computers were large and expensive. In 1964, Digital Equipment Corporation (DEC) introduced the PDP-8, which is widely regarded as the first "minicomputer". There was an earlier one from CDC(yes, from the "bunCh), the CDC 160 in 1960- which was the size of a table. DEC itself had PDP 5 which was smaller and cheaper than the large mainframes. To understand the price difference -- a typical mainframe was priced between $100k and $ 1M ( $850k to $8.5M in today's value) while the DEC PDP-8 started at around $25K ($212K in 2021) . DEC, CDC and others like Data General (DG), Wang created machines in this segment for about 25 years.

These machines were bought by labs and research departments of universities - which earlier had to fight for time on the large mainframes for any kind of meaningful research. The early versions were built using transistors (then an emerging technology) and magnetic core memory. In the seventies they switched to early microprocessors and silicon memory. The early PCs (such as Altair, ~1974) were still called "minicomputers".

Magnetic core memory is another fascinating piece of early computing technology which deserves a separate post.

These machines were around till well into the 80s- quite a few PDP-11s were there in India as well. These machines gave an option of using Unix or DEC's own OS, Vax/VMS ( which heavily influenced the design of?#Windows?NT)

The last of this breed were probably the Sun Sparc and IBM AS-400. SPARC servers are still sold by Oracle-- and the IBM iSeries is the descendant of the?#AS400. These are called "mid-range" , I believe.

DEC was bought by Compaq in the 1990s, DG, Wang etc died along the way.

In 2021, when a young C developer encounters a "Core dump", he/she is actually getting a message from the earliest versions of?#Unix?and?#Clanguage?which were developed on these DEC PDP machines, all the way from the 1960s!!! (Wonder why Torvalds retained the message.)

6.??????Dec 2021— Spreadsheets and PCs

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In the early days of PCs (before Apple ii) ,these computers were used by hobbyists and enthusiasts. Most people didn't know what to do with these cool devices. All that changed when VisiCorp created VisiCalc for Apple ii, the first spreadsheet program from PCs. In fact, the phrase "Killer app" was first used for Visicalc, as it powered the sales of PCs.

The history spreadsheet programs is closely associated with the development of the PC. The IBM PC was powered by the Lotus 123, a very fast spreadsheet created by Mitch Kapor--who also created Lotus Notes in the late 80s, which had a hypertext protocol-- a precursor to the current HTTP protocols. Lotus was the dominant application on the PC till GUI came on and Excel replaced it.

The story goes that Spreadsheets helped finance guys enormously and because of that they began approving PC purchases!!-- and that is what gave the boost to PC sales to businesses in the early days.

Excel first appeared on the the Macintosh in 1985 or 86 , , almost a decade before Windows 95. (I had seen a demo of this in 1987 in Delhi, when Apple had demonstrated their computers at an event-- it that was was my first encounter with GUI (or WIMP as it was called then -- Windows, Icons, Menus, Pointers ( I think)).

Of course, now it is something everyone takes for granted. Most of the original ones Visicalc, Lotus, Supercalc etc are dead and gone, and Excel rules this space.

Excel's language has now evolved into a Turing complete one, but I don't see many takers for that!!