Simple text examination and listing. The larger and better known search engines seem to operate by looking for user entered search words in local copies of WWW pages. Complex and multi-word queries are often possible and results are frequently ranked for relevance although the significance of the relevance measures is rarely described. The person making the query is presented with a list of pages, sometimes with abstracts. The WWW is essentially, in computer science jargon, stateless, which means the search engine cannot simply remember the user's previous query or queries, although the better engines use various slightly clumsy techniques to overcome this problem on a short term basis.
Classification is ad hoc when attempted at all.
There are number of classified listings, particularly of commercial sites, available. However the classifications are often quite arbitrary and at the whim of the list compiler. Most such listings are quite small and the rationale for inclusion of a particular WWW page is unclear. A proper classified listing, preferably using some recognised scheme, would be a great boon to both commercial organisations looking for suppliers and academics researching particular topics. Non-English text causes problems.