What is Search Engine? And know about some Search Engines

The search engine is a program that collects information from various web sites in the world and when a user searches for a keyword the information related to this program provides website link from the database. The information may be a mix of web pages, pictures, and other types of files. Some search engines also quarry data available in databases or open directories. Different web sites are sustained by human editors and search engines also sustain real-time information by running an algorithm on a web crawler.