How to work search engines?
 

How to work search engines?

Some websites stop web crawlers from visiting them. These pages will be left out of the index, along with pages that no-one links to. The information that the web crawler puts together is then used by search engines. It becomes the search engine's index.

The information that the web crawler puts together is then used by search engines. It becomes the search engine's index.

There are three basic stages for a Search Engine:
Crawling: Where content is discovered
Indexing: Where it is analyzed and stored in vast databases
Retrieval: Where a user inquiry makes a list of related pages

The information that the web crawler puts together is then used by search engines. It becomes the search engine's index.

Using Google Algorithm...

How is a website crawled exactly? An automated bot – a spider – visits each page, just like you or I would, only very quickly. Even in the earliest days, Google reported that they were reading a few hundred pages a second. If you’d like to learn how to make your own basic web crawler in PHP – it was one of the first articles I wrote here and well worth having a go at (just don’t expect to make the next Google).

Search engines have two major functions: crawling and building an index, and providing search users with a ranked list of the websites they've determined are the most relevant.Links allow the search engines' automated robots, called "crawlers" or "spiders," to reach the many billions of interconnected documents on the web.Once the engines find these pages, they decipher the code from them and store selected pieces in massive databases, to be recalled later when needed for a search query. Search engines are answer machines. When a person performs an online search, the search engine scours its corpus of billions of documents and does two things: first, it returns only those results that are relevant or useful to the searcher's query; second, it ranks those results according to the popularity of the websites serving the information.

There are three basic stages for a search engine: crawling – where content is discovered; indexing, where it is analysed and stored in huge databases; and retrieval, where a user query fetches a list of relevant pages.

Some websites stop web crawlers from visiting them. These pages will be left out of the index, along with pages that no-one links to. The information that the web crawler puts together is then used by search engines. It becomes the search engine's index.,

There are three basic stages for a Search Engine:
Crawling: Where content is discovered
Indexing: Where it is analyzed and stored in vast databases
Retrieval: Where a user inquiry makes a list of related pages