Structured forms based searching. Note, however, that many pages relevant to Australia and New Zealand are not in the .nz or .au domains. Accepts natural language queries, and matches them to the database. We'll assume that 20 relevant items exist on the Internet. Any search is a compromise between precision and recall, and the balance depends on the user's needs.
People tend to assume that a high precision means a good search.
In fact this may indicate low recall. It's hard to determine recall, since we don't know how many relevant items we've missed. Check for mis-spelt words, or american terminology. Metasearch engines Metasearch engines, or combined search engines, search across several search engines. A disadvantage is that you can't take advantage of the special features of a particular search engine, and you may only be shown the first few from each search engine.