Vertical search, part of a larger subgrouping known as "specialized" search, is a relatively new tier in the Internet search industry consisting of search engines that focus on specific businesses.
The term "search engine" refers to a software program that searches the Web and Usenet groups to find documents containing one or more specified keywords, and returns a list of documents in which the keywords were found.
Broad-based search engines such as Google or Yahoo fetch very large numbers of documents using a Web crawler. Another program called an indexer then reads these documents and creates a search index based on words contained in each document. Each search engine uses a proprietary algorithm to create its indexes so that, ideally, only meaningful results are returned for each query.
Vertical search engines, on the other hand, send their spiders out to a highly refined database, and their indexes contain information about a specific topic. As a result, they are of most value to people interested in a particular area; what’s more, the companies that advertise on these search engines reach a very focused audience. For example, there are search engines for veterinarians, doctors, patients, job seekers, house hunters, recruiters, travelers and corporate purchasers, to name a few.
