SEO Notes – Understanding search engine working

All search engines contain the following main components.

1. Crawler program to follow the links on each webpage. Its task is follows the links and scan the documents and web pages.
2. Spider is a program that downloads web pages on instructions of crawler. It does not have any visual components and works directly with the underlying HTML code of the page.
3. Indexer analyzes web pages downloaded by the spider. It parses each page and analyzes the various elements, such as text, headers, structural or stylistic features, special HTML tags, etc.
4. Database– storage for downloaded and processed pages
5. Results engine – extracts search results from the database. Is one of the important components as this determines which pages best match a user’s query and in what order the they should be listed.
6. Web server – a server that is responsible for interaction between the user and other search engine components.