JavaScript

Event-driven, Functional, Imperative

In this article, you will find better understandings and basic knowledge of JavaScript helps to acquire information in a simple way as well as easy to learn.

JavaScript is a high-level, dynamically typed, interpreted language. It uses Java-like syntax, hence the name JavaScript. JavaScript is used to write code that runs in web browsers, on the client-side. If you’ve been using the Web long enough to remember the introduction of Google Maps, you witnessed some of the first magic, the “infinite scrolling” in Maps is done using JavaScript.

Since its first introduction, JavaScript support has been added to all major web browsers. JavaScript frameworks including React, Angular, and Vue offer a Model-View-Controller application development paradigm, running entirely in the browser. JavaScript now supports the visual, browser-run elements of most modern web applications, which is why most real user monitoring tools cater to JavaScript.

JavaScript can also be combined with HTML to make cross-platform mobile applications. NodeJS is a web server that runs JavaScript on the server-side. NodeJS applications are written entirely in JavaScript.

Brief History:-

Early mainframe computers (in the 1950s) were non-interactive, instead of using batch processing. IBM’s Job Control Language (JCL) is the archetype of languages used to control batch processing.

The first interactive shells were developed in the 1960s to enable remote operation of the first time-sharing systems, and these used shell scripts, which controlled running computer programs within a computer program, the shell. Calvin Mooers in his TRAC language is generally credited with inventing command substitution, the ability to embed commands in scripts that when interpreted insert a character string into the script. Multics calls these active functions. Louis Pouzin wrote an early processor for command scripts called RUNCOM for CTSS around 1964. Stuart Madnick at MIT wrote a scripting language for IBM’s CP/CMS in 1966. He originally called this processor COMMAND, later named EXEC. Multics included an offshoot of CTSS RUNCOM, also called RUNCOM. EXEC was eventually replaced by EXEC 2 and REXX.

Languages such as Tcl and Lua were specifically designed as general-purpose scripting languages that could be embedded in any application. Other languages such as Visual Basic for Applications (VBA) provided strong integration with the automation facilities of an underlying system. Embedding of such general-purpose scripting languages instead of developing a new language for each application also had obvious benefits, relieving the application developer of the need to code a language translator from scratch and allowing the user to apply skills learned elsewhere.

Some software incorporates several different scripting languages. Modern web browsers typically provide a language for writing extensions to the browser itself, and several standard embedded languages for controlling the browser, including JavaScript (a dialect of ECMAScript) or XUL.

Features Of JavaScript:-

1. Object-Centred Script Language

Object Centered Language features built in the object as Java Script has a window object. Some Common Examples of Object Centered languages are JavaScript and Visual Basic etc. The object-centred languages are mostly used for features like Polymorphism which is a quality of taking an object in many forms. Use of Polymorphism within object-oriented programming requires whenever we use to represent reference of the parent class to an object of a child class.

2. Client Edge Technology

The client is basically a term used for Web Browser in respective of User. The data on the server gets uploaded by a client which later used by a user in the rendered form. The user gets access to the client through a web browser for surfing and interacting through websites. The client edge technology in Java Script allows the client to have full control over the content which is being updated in servers.

3. Validation of User’s Input

Validation of User’s Input is most commonly known as form validation, it allows users to interact with client through filling forms through web pages. The details in the form need to be correctly filled where form validation helps the client to validate the details entered by the user.

4. Else and IF Statement

IF and Else Statements are used to perform logical operations.

5. Interpreter Centered

Java Script is built with Interpreter Centered which allows the user to get the output without the use of Compiler. That means the input performed by the user gets rendered directly without the compiling of codes.

6. Ability to Perform In Build Function

Java Script has many In-Built Functions like isNAN(), Number(), parseFloat() and parseInt() etc. isNAN() Function is used to identify that input object is correct number format. parseFloat() function is used in the conversion of the object into a number. parseInt() Function is used to analyze strings.

7. Case Sensitive Format

The codes written in Java Script are Case Sensitive which explains that there will be no difference in the output whether the codes are written in Upper Case or Lower Case Format.

8. Light Weight and delicate

Java Script Features Light Weight and delicate and codes written in JavaScript don’t include variables and uses only objects to perform the operations.

9. Statements Looping

The statement looping is used to perform the same operations repeatedly. In this operation the same set of code run in repeat manner for a specific or unspecific set of time.

10. Handling Events

The Java Script has the ability to control operations updated on servers. This is basically controlling the response on the website when the user tries to perform any operation the server handled by the client like clicking on links and options, interaction response over the website, etc.

Applications:-

JavaScript is mainly used for web-based applications and web browsers. But JavaScript is also used beyond the Web in software, servers and embedded hardware controls. Here are some basic things JavaScript is used for:-

1. Adding interactive behaviour to web pages

JavaScript allows users to interact with web pages. There are almost no limits to the things you can do with JavaScript on a web page these are just a few examples:-

Show or hide more information with the click of a button

Change the colour of a button when the mouse hovers over it

Slide through a carousel of images on the homepage

Zooming in or zooming out on an image

Displaying a timer or count-down on a website

Playing audio and video on a web page

Displaying animations

Using a drop-down hamburger menu

2. Creating web and mobile apps

Developers can use various JavaScript frameworks for developing and building web and mobile apps. JavaScript frameworks are collections of JavaScript code libraries that provide developers with pre-written code to use for routine programming features and tasks — literally a framework to build websites or web applications around.

Popular JavaScript front-end frameworks include React, React Native, Angular, and Vue. Many companies use Node.js, a JavaScript runtime environment built on Google Chrome’s JavaScript V8 engine. A few famous examples include Paypal, LinkedIn, Netflix, and Uber.

3. Building web servers and developing server applications

Beyond websites and apps, developers can also use JavaScript to build simple web servers and develop the back-end infrastructure using Node.js.

4. Game development

You can also use JavaScript to create browser games. These are a great way for beginning developers to practice their JavaScript skills.