Information search systems are one of the most important Internet services because they allow the immense knowledge potential of the Internet to be used efficiently and in a timely manner.
The Internet offers, among others, the information search programs Gopher, World Wide Web(WWW) and Wide AreaInformationServer( WAIS). Each of the three search programs uses different search algorithms, making each suitable for different applications. All three programs are based on the server- client principle; the search takes place on the corresponding servers. The search is controlled by the user (client) with the help of a corresponding client program.
The three information search programs are available free of charge on the Internet for all common operating systems. Gopher and WAIS are used less frequently, since WWW clients can also access Gopher and WAIS servers.