In early 1995 the World Wide Web and graphical web browsers were brand new, and Netscape Communications Corporation was leading their development. Netscape wanted a small scripting language that ordinary page authors could embed directly in HTML, to complement the heavier Java language. Brendan Eich, who had joined Netscape on April 3, 1995, was given the job of proving it could be done.
Under heavy deadline pressure ahead of the Netscape Navigator 2.0 beta, Eich built a working prototype, code-named Mocha, in about ten days in May 1995. The history “JavaScript: The First 20 Years,” which Eich co-authored, records that he “prototyped the first Mocha implementation in ten contiguous days in May, 1995,” and that he believes the dates were roughly May 6 to 15. At the end of those ten days the prototype was demonstrated to the full Netscape engineering staff.
The language first reached the public in September 1995 under the name LiveScript, bundled in the first beta of Navigator 2.0. Then, on December 4, 1995, Netscape and Sun Microsystems issued a joint press release announcing the language under its now-famous name, JavaScript, and positioning it as a “complement to Java for easy online application development.”
The rushed ten-day origin left lasting quirks in the language, but it also produced what would become the universal language of the web. Standardization followed quickly, beginning in 1996 and yielding the first ECMAScript standard in 1997.