About NCSA Mosaic for the X Window System

NCSA Mosaic for the X Window System is a networked information discovery, retrieval, and collaboration tool and World Wide Web browser developed at the National Center for Supercomputing Applications.

Due to the TREMENDOUS load being handled by the NCSA WWW server there may be times that you are unable to get the NCSA Mosaic Home Page when you first start Mosaic. This in no way should effect your ability to retrieve documents from other sites. To alleviate this problem you may want to set an alternate home page for Mosaic to automatically load on startup.

For information on how to use NCSA Mosaic for X, see:

Also see the NCSA Mosaic demo document and What's New.

For the security minded read about Mosaic Security Concerns.

Current Version Is 2.4!

Please note that the current released version of NCSA Mosaic for the X Window System is version 2.4. If you are running an earlier version, please upgrade.

Please also note that the online documentation is not yet updated for version 2.x. In the interim, see help on version 2.0.

Credits and Copyright

NCSA Mosaic is a product of the Software Development Group of the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign.

NCSA Mosaic is copyrighted but free for academic and research use. See the NCSA Mosaic copyright.

The NCSA Mosaic for X developers are Eric Bina and Marc Andreessen:

Thanks to Tim Berners-Lee and the other CERN World Wide Web wizards for the WWW client library code and all of their other work on the WWW project, and to everyone out in netland who has contributed to Mosaic's development either directly (through comments or bug reports) or indirectly (through inspiration and development of other systems).


You can retrieve copies of NCSA Mosaic in both source and executable binary form from NCSA's anonymous FTP server, ftp.ncsa.uiuc.edu.

Problems or Comments

If you have problems or comments concerning NCSA Mosaic, please first read the documentation and the FAQ list; if they don't answer your question or resolve your complaint, send your comments to mosaic-x@ncsa.uiuc.edu. (You can also use the Mail Developers option under the Help menu.)

Please also send a note if you find NCSA Mosaic useful or particularly interesting -- we want to hear from you.