A crawler is a type of software program used by search engines like Google to explore and index content on the internet. It systematically navigates web pages by following links, gathering information about the content, and storing it in a database. This process helps search engines understand what each page is about, making it easier for users to find relevant information. In addition to search engines, crawlers are also used in various applications, such as data mining and web scraping. They can collect data from websites for research, analysis, or competitive intelligence. Crawlers play a crucial role in how information is organized and accessed online.