WAIS (wide area information service) is based on indexed searches. Rather than searching documents, it searches indexes, much the way you would search a card catalog in a library instead of searching through each book. When you first use WAIS to begin a search, you will search a list of indexes to find one that would be likely to describe documents you are looking for. In the library analogy, this search would help you identify the library (main library, science library, public library) that is most likely to have the information you want. Having found an index, you can then search it to find documents based on keywords. WAIS has several interesting features, including the ability to save previous searches so it becomes easier to use the more you use it, but the searches are rather limited (e.g. you can't say ``search for papers with keywords `logic' and `programming' but not `Prolog'''). WAIS is available through gopher, so if you already know the gopher interface it should be straightforward to expand your view of the network and use gopher to start searching ``card catalogs'' via WAIS.