The concept of accessing data online in the form of websites and hyperlinks had just started to hit the highway when computer scientist Tim Berners-Lee invented the world wide web in 1989. He was the first person to write a web browser (in 1990).
In 1992 and after
A browser called NCSA Mosaic (simply Mosaic) was developed at the National Center for Supercomputing Applications (NCSA) which later on popularized the web and the internet with its support for multiple internet protocols like FTP, Network News Transfer Protocol, and Gopher. It was also the first browser to display images inline with text instead of displaying images in a separate window (In 1993).
After the success of the Mosaic web browser, Marc Andreessen a part-time employee of the NCSA and one of the co-writers of the browser itself was inspired by the potential of Mosaic in the commercial world, who later on founded Netscape Communications Corp and came up with the Netscape Navigator browser. During development, the Netscape browser was known by the code name Mozilla, a portmanteau of “Mosaic and Godzilla”.
Mosaic had started loosing market shares to Netscape Navigator due to Netscapes innovative features (from 1994) like on-the-fly display of web pages, where text and graphics appeared on the screen as the web page downloaded. Earlier browsers would not display a page until all graphics on it had been loaded over the network connection; this often made a user stare at a blank page for as long as several minutes.
The web back then was only static and HTML was still too young. With the vision of making the web more dynamic and providing easier access for developers and designers, the idea of Mocha was born. Mocha was to become a scripting language for the web.
Brendan Eich was contracted by Netscape Communications with the goal of embedding the Scheme programming language into its Netscape Navigator.
Netscape Comminications at that time had joined hands with Sun Microsystems to make Java available in the browser. But, Java (enterprise level) was not suited for the type of audience that Mocha would consume: designers, scripters etc. Hence, A decision was made such that Java would be made available for professional developers while Mocha would be used as a Java sidekick for small scripting tasks. However, they all lacked time. Why ?
Microsoft had already entered the web browser software market with Internet Explorer by licensing the Mosaic source code from Spyglass, Inc ( which in turn licensed code from University of Illinois).
ECMAScript standard helps ensure consistency between Netscape, Microsoft and any other web script implementations.