Specialized hypermedia corpuses.
A variety of hypermedia materials are becoming available and these collections are often served from a library rather than dedicated machines in classrooms. In many sites, Perseus is delivered through a campus network. In some sites, Perseus is provided on a stand-alone machine in a library. The many CD-ROM corpuses now available for specialized topics challenge schools and individuals to be judicious in acquisition and use of these materials, thus increasing the need for resource sharing functions of libraries. As vendors develop new products and as these specialized corpuses become available through global networks, libraries should take responsibility for ensuring secure and legal usage by students and teachers.