A search engine works in two main parts. Both of these parts combined make up its database and deliver the results when you type in a keyword into the search box. These two main parts are the indexer and the crawler.
The first main portion of a search engine is the crawler.
This is also called a spider or a bot. For the sake of this article will use the term spider since this is what most people are used to. The spiders main function is to go out on the Internet and crawl the millions upon millions of websites that are online. It does this by taking a primary source such as Wikipedia. It crawls all of the pages within Wikipedia, and then follows all the links that it finds. For instance, let’s say it crawls a page on Wikipedia about Camaros. It then goes to one of the source links for that page which may be Chevys.com. The spider program will then go to Chevys.com and follow the links on that page and index those into its database. Now Let’s say on Chevys.com there was a link to Bob’s garage. The spider program will follow that link from Chevys.com to Bob’s garage and index all the pages off of that site, and so forth. As you can imagine this program runs continuously, and gathers extremely large amounts of data which it brings back into its database. This database is what comprises the main portion of the search engine.
The next main component of the search engine is the indexer.
The indexer’s main function is to take all of the data that the spider program has found and turn it into sensible information, that is delivered to you when you do a search. When you go to a search engine such as www.Tellagin.com and do a search, the indexer scours its entire database and tries to match as closely as possible the keyword you typed in, with what is in its database. For instance, if you do a search for the word cars the indexer will search its database using its unique algorithm and find as many relevant matches for the word cars as possible. It will then deliver these results to you, all within fractions of a second. Together, the indexer and the crawler work in harmony to build up the search engine’s database and to deliver the results when a search is performed. Millions upon millions of people utilize search engines every day for every aspect of their life. Whether finding a doctor, a babysitter, or a restaurant, search engines provide all the information that we need.