What to know about JavaScript

A computer program is simply a series of instructions intended to tell the computer how to perform a task. Unlike humans, computers only understand 1s and 0s. Machine codes and assembly language are low-level programming languages that are closely related to the machine’s hardware and architecture.

Alternatively, high-level programming languages such as C,C++, C# or Java allow abstraction codes to used, making code easier for humans to write and read .These are compiled to assembly language codes or machine codes to be executed.

High-level languages which are translated to machine codes at run time are referred to as scripting languages. An example of such language is JavaScript.

JavaScript is mostly referred  to as the language of the Web. Nearly all browsers can run JavaScript. All that is needed to run it is a text editor and a web browser. It is very flexible and expressive that can be used to achieve very powerful application developments.

As a scripting language, it is compiled at run time. Most common JavaScript engines, responsible for interpreting programs and running them, can be found in browsers such as Chrome, Internet Explorer or Firefox. Many modern engines use a as Just-in-time (JIT) interpreting process to considerably speed up the compilation process. This makes the programs run faster.

The World Wide Web (WWW)  started as a bunch of pages linked together by hyperlinks. Borrowing other language elements including Java, Perl, Scheme, HyperTalk, AWK and Self, Brendan Eich developed a new language for the Netscape browser. It was originally called LiveScript but was later re-branded as JavaScript. The naming has often been a center for controversy that JavaScript is a lighter version of Java. Though the 2 share some syntax, they are unrelated.

In 1996, Microsoft reverse-engineered JavaScript to create JScript. Whiles JavaScript was shipped with Netscape’s Navigator browser, JScript was shipped with Internet Explorer version 3. At that time, Microsoft included another scripting language called VBScript with Internet Explorer.

Due to its early poor usage, Netscape and Sun Microsystems decided to standardize JavaScript along with the help of European Computer Manufacturers Association. This led to ECMAScript, the standardized version. Eventually, ECMAScript was often used to refer to the specification whereas JavaScript was still (and currently) used to refer to the languages itself.

In 2005, sophisticated sites such as Google Maps, Gmail demonstrated that JavaScript was capable of being used to create very powerful applications. Around that time, Asynchronous JavaScript and XML (AJAX) was coined by Jesse James Garret. This technique was used to obtain data from a server in the background and for updating only the relevant parts of the web page without refreshing the full page. This enabled more user interactivity. As a result, JavaScript gained popularity.

In 2008, engineers at Google developed the V8 engine to run within Chrome. It was significantly faster than earlier engines. Many vendors responded by increasing their JavaScript engines’ speed. Today, the pace of improvement with respect to JavaScript is on the rise with many modern browsers running JavaScript significantly faster.

Today, a big growth area for JavaScript is Single Page Applications. These applications run in the browser and rely heavily on JavaScript. An example of such a framework is Angular JS. Also, as the graphical capabilities of browsers are improving, the dawn of HTML 5 with the use of JavaScript is just awakening. JavaScript can also be used to develop browser extensions. It is even used as the scripting language for many non web-related applications.

JavaScript has a bright and nice future. As the web platform is evolving, JavaScript will remain a central part of its history and future.

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