Mosaic is a web browser (client) for the World Wide Web written at the National Center for Supercomputing Applications (NCSA). Its development began in 1992 and officially ceased on January 7, 1997.
Mosaic was described as "the killer application of the 1990s" because it was the first program to provide a slick multimedia graphical user interface to the Internet's burgeoning wealth of distributed information services (formerly mostly limited to FTP, Usenet and Gopher) at a time when access to the Internet was expanding rapidly outside its previous domain of academia and large industrial research institutions.
NCSA Mosaic was originally designed and programmed for Unix's X Window System by Marc Andreessen and Eric Bina at NCSA. Development of Mosaic began in December 1992. Version 1.0 was released on April 22, 1993, followed by two maintenance releases during summer 1993. Version 2.0 was released in December 1993, along with version 1.0 releases for both the Apple Macintosh and Microsoft Windows. An Acorn Archimedes port was underway in May 1994.
The licensing terms for NCSA Mosaic were generous for a proprietary software program. For all versions, non-commercial use was generally free (with certain limitations). In addition, the X Window System/Unix version publicly provided source code (source code for the other versions was available after agreements were signed). However, despite persistent rumors to the contrary, Mosaic was never released as open source software during its brief reign as a major browser; there were always constraints on permissible uses without payment.
The leader of the team that developed it, Marc Andreessen left NCSA with Jim Clark, one of the founders of Silicon Graphics, Inc. (SGI) along with four other former students and staff of the University of Illinois and started Mosaic Communications Corporation which became Netscape Communications Corporation, producing Netscape Navigator.
Spyglass licensed the technology and trademarks from NCSA for producing their own web browser but never used any of the NCSA Mosaic source code.  Spyglass Mosaic was later licensed by Microsoft, and it was modified and renamed Internet Explorer.
Mosaic's popularity as a separate browser began to dry up upon the release of Netscape Navigator, and by 1998 its userbase had almost completely evaporated.
Last updated: 05-25-2005 08:19:48