Search system – SEO WIKI
A search engine (or the so-called “search engine”) is a computer system designed specifically to search for the necessary information on the Internet. The most common application is services for searching text and graphic content, as well as files on FTP servers, goods in online stores, etc.
To find something specific, you need to enter a search query. Further, the system searches for documents by key phrases, or words, somehow related to keywords. During this, the search engine generates a page with search results. The output contains not only text content, but also images, as well as audio files.
The usefulness of search engines depends on the relevance of the Internet pages that they return. Yandex and Google are the most popular search engines in our country.
Types of Search Engines
A crawler (robot) bypasses the network, the index contains a huge archive of copies of Internet pages, and the software scans the search results. Many modern search engines are of this type.
Directories of Internet resources.
These types of search engines receive lists of web pages. Directories include the address, title, and brief information about the Internet resource. Directories only search for results from page descriptions provided by webmasters. The advantage of directories is in manual verification of sites, which directly affects the quality of content. In this case, it will be higher than the results automatically processed by the first type of search engines.
Search engines such as Google and Yahoo combine 2 types of search engines (search engines, and systems that people control).
Metasystems (or multi-threaded systems).
They do not have their own database and search index. They form the result by re-arranging the results of other search engines. In those days when search engines were not so smart and had their own unique address, this type of search engine was considered useful.