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Mosaic Web Browser

Last Edit: 18/08/17

Mosaic was an early Web browser, released in 1993, which is credited with rapidly expanding the popularity of the World Wide Web. Mosaic is usually described as being the first graphics web browser: due to it being able to display text and images on the same page, instead of each image being loaded in a separate page. While Mosaic was not the first web browser, it was the first browser that looked like, and contained features, found in every subsequent browser: such as icons and bookmarks. Mosaic is generally acclaimed as the first professional web browser, that overcame many of the shortcomings of the first web browsers; before it was released, the World Wide Web was probably used by tens of thousands, within a year of its release, the Mosaic browser was being used by millions. Without the creation of the Mosaic web browser, it is within reason to assert that other information systems, such as Gopher, instead of the Web, would have dominated the Internet.

a screenshot of the mosaic web browser, showing the address bar and common functions

The Mosiac web browser was one of the first browsers to display graphics, and for helping to make the web popular.

The user interface of the Mosaic web browser, released on April 22nd 1993

The Mosaic project was started by Marc Andreessen and Eric Bina, who were members of the Software Design Group at the National Center for Supercomputing Applications (NCSA); which operates a facility at the University of Illinois at Urbana-Champaign. In 1992, Dave Thompson, a colleague at NCSA, downloaded an early web browser - Joseph Hardin believes it was a SLAC browser - struggled, but eventually got it working, and showcased it to Marc Andreessen and Joseph Hardin. While impressed by the World Wide Web, Marc Andreessen and Joseph Hardin believed a better browser could be designed: due to the "terrible" interface of the SLAC browser and the difficulty of getting the browser working. Marc Andreessen and Eric Bina set about creating a new browser that would work on every X Windows box - unlike the SLAC browser - and a number of prototypes were designed: such as the XMosaic WWW client. The official launch date for the Mosaic web browser was April the 22nd 1993: Mosaic v 1.0 was free to download from its website, and the Mosaic website stated that 5,000 copies were being downloaded each month in 1993. By 1994, the Mosaic browser had a user-base of several million users; according to the archive of the Mosaic website (

Due to the success of the browser, James Clark, a Silicon Valley entrepreneur, persuaded Marc Andreessen to leave NCSA, and with William Foss, they founded the Mosaic Communications Corporation on April 4th 1994. The new venture was located at Mountain View, California, and Andreessen recruited many of the key programmers of the NCSA Mosaic browser to join him in California. The first browser the company released was the Mosaic Netscape 0.9 browser; released on October 13th 1994. While Mosaic Netscape 0.9 did not share any code of the original NCSA Mosaic browser, it was designed by the same personal. Due to copyright issues, the Mosaic Netscape 0.9 browser was eventually renamed to Netscape Navigator, and the corporation was renamed to Netscape Communications Corporation. Netscape Navigator was the most popular browser until Microsoft packaged Internet Explorer with Windows 95. The success of Netscape Navigator, and the loss of personal, led to the demise of the original NCSA Mosaic browser; NCSA officially announced the closure of the project in January 1997.

Netscape Communications was purchased by AOL in 1998; even though AOL continued to fund the development of the Netscape browser, its market share continued to dwindle throughout the 2000s, until its overall market share was under 1%. The Mozilla Foundation was founded in 1998 and was created as a "spiritual heir" for the original Netscape Navigator browser. The word "Mozilla" is believed to have been coined by the Mosaic Netscape 0.9 programmers, who termed their new browser a "Mosaic Killer". Therefore, if any current browser is the 'heir' of the original NCSA Mosaic browser it would be the Mozilla Firefox browser; while it shares no code, its viewed as the "heir" of Netscape Navigator, which was the "heir" of the Mosaic Netscape 0.9, which was designed by programmers who had designed the NCSA Mosaic browser.