3.1.1 Commercial search engines

Commercial search engines are divided into four categories:

• Standard: the most well known search engines such as www.google.com, www.bing.com, http://www.ask.com/. They are looking for any kind of in-formation through the Internet and are characterized by a very light interface (mostly text-based applications):

Ask search engine home page

• Portals: Portals are a mix between standard search engines and directories. Differently from search engines, directories are using human being instead of robots to index websites address. In theory (if we did not take into consideration the commercial aspect) directories should provide quality information rather than quantity. (Friedman, B. G. (2004). Web Search Savvy. p.21) Portals are then characterized by a lot of information on their home page including the search engine func-tion. The most well known portal is Yahoo.

Yahoo home page

• Specialized search engines: they belong to a subcategory of the first group and are also called vertical search engines. Vertical search engine is to search the information sources of one industry or a kind. (Wang, W. (2007). Integration and Innovation Orient to E-Society Volume 1. p.666) Specialized search engines are crawling only a restricted area and not the entire web. For example they can search only in a specific website or only a specific kind of document (books, images, .pdf documents, videos…).

If specialized search engines are not a revolution in themselves (they are for most of them a filter of bigger search engines) they however find their

place when standard search engines are providing too many results for a given request.

An example of vertical search with Yahoo Images

• Semantic search engines: Most of search engines on the market are based on keywords and documents popularity (for example Google page rank) without taking into account the real content. (Priss, U./Corbett, D./Angelova, G. (2002). Conceptual structures. p.92) The idea behind se-mantic is to understand the hidden meaning of the information. A recent example of such search engine called "Wolfram Alpha" just came out on the market, qualified as a "knowledge engine" (Valentiner, Z. (2009). New search tool on the block: Wolfram Alpha.) designed to give you answers to your request rather than driving you to a website which may have it. Semantic search engines belong to the Web 3.0 generation where machines interpret the meaning of the data. (Cf. Sankar, K./Bouchard, S./Mancini, D. (2009). Enterprise Web 2.0 Fundamentals. P.161)

A semantic search engine: Wolfram Alpha