The University of Illinois at Urbana Champaign's supercomputing center, NCSA, has developed a large number of popular software packages, such as NCSA Telnet. In 1993 they release NCSA Mosaic, first on Unix and then on Mac and PC systems, for browsing on the World-Wide Web and to also work with other Internet information protocols such as gopher and FTP. This has emerged as the "killer app" for the Internet that has stimulated millions to use it and the WWW. Numerous commercial spin-offs have resulted, and there is an active conference series for the WWW with large events twice each year.