

The new developers attracted to the project decided that the underlying code was outdated and decided to rewrite it from scratch. This is because version 5 of the browser was in development when the program was GPL'ed. The Netscape series of web browsers skips over the version 5 designation. This would be the last commercial Netscape web browser, as dwindling market share forced Netscape Communications Corporation to release the code base for the browser under the GPL open source software license. Netscape Navigator was renamed Netscape Communicator for its version 4.0 release. Thus, more and more sites were incompatible with Netscape and therefore more people switched to IE or alternatives such as Opera. As Internet Explorer gained market share due to its inclusion in Windows, more and more webmasters coded for IE. Thus, websites were forced to choose between either Netscape or IE, or to forfeit advanced features such as image support, JavaScript, and cookies. Notably, Microsoft's Internet Explorer also included many proprietary extensions that provided similar functionality, but were not compatible with the Netscape extensions. However, webpages that took advantage of these proprietary features did so at the price of standards compatibility and thus those sites did not display properly on other web browsers. Proprietary extensions to the HTML markup language and various interface innovations made the browser much more functional that the published standards allowed.

While the first version of Netscape Navigator adhered very strictly to World Wide Web standards, later versions pushed the limits of network technology. As the success of Navigator was dependent upon its exclusivity, the inclusion of Internet Explorer in Windows led to a rather speedy demise in Navigator's dominance. As no web browser was included with either Microsoft Windows nor Macintosh operating systems at the time, Navigator was often the only available choice. Although proprietary software, Navigator was offered for free download and was often included with ISP software packages. Developed and marketed by Netscape Communications Corporation as an easy to use product, Netscape Navigator is credited with bringing the Internet within easy reach of the average computer user.

Netscape Navigator was the dominant web browser during the early years of the Internet.
