Searching the Internet
To use a search engine, it is quite easy. Just type in keywords relating to the site you are looking for and
click on search. Many sites have advanced features, such as searching for phrases instead of collections of
words, searching for several words but not others, and a few will even attempt to correct spelling mistakes.
Below is my personal favorite engine, Google.
The 'I'm Feeling Lucky' button simply takes you directly to the first hit you get on your search terms. (In theory
the most likely place to find what you are looking for.) You can specialize your search by putting quotes "
around your search terms to form a 'phrase'. Under advanced search you can tell it words not to find, to match
all or some of your search terms, etc. Most search engines have similar options.
The Internet is a large collection of millions of sites buried in obscure URL's. Without search engines no one
would be able to find anything. There are approximately 30 major search engines; all of them are not listed on
our pull down menu for various reasons. Each search engine does things a little differently, and it is not
unusual for people to prefer one over others, but when you are searching for something specific, sometimes
it is good to use several.
There are three major types of search engines on the web:
There are of course other methods used for indexing content (For example, Overture.com rates commercial content
based on how much they pay to 'have' a keyword).
- Content-Index - Of which Yahoo is the best known example. Yahoo searches through a list of sites indexed by site type. These sites are viewable on Yahoo's site by going to the specific category you want (such as Automotive > For Sale). Each site is accepted into Yahoo's 'family' by Yahoo's very large staff of site checkers, which rate each site submitted to Yahoo based on internal criteria, and decide on it's inclusion. These types of engines sometimes have better resources than others, but not nearly as broad a coverage of any particular subject. Another search engine in this category is MSN, though it also uses a Spider-Index, just gives it lower priority. (see below)
- Spidered-Index - Google and AltaVista are the best known examples of this type of search engine. Both of them, instead of indexing by specific content of the page, search based on Keywords included in each webpage, by accessing a database build by a web spider, an automatic program that goes to a website, such as www.vallnet.com, reads it, and follows all then links on the site to gain more pages to index. Each search engine rates each site by keyword, and attempts to send you the best match for what you type into the search box.
- Meta Search - Metacrawler is one of the best known 'Meta' search engines. These search engines do not have any indexes of their own, instead, the send your query to several other search engines (Google, Yahoo, Altavista are popular) and rate the overall result based on responses from all of them (results returned by many rate higher than results returned by one)