A “crawler,” also known as a “web crawler” or “spider,” is a program or script that systematically browses the internet, visiting web pages and collecting information to index and update search engine databases. Crawlers are a fundamental part of search engine operations, helping search engines discover and analyze the content of websites. 


A crawler is an automated program or script that navigates the internet, visiting web pages, and systematically collecting data for indexing by search engines. It is an essential component of the search engine process.

Think of a crawler as a diligent explorer that travels across the internet, visiting websites, reading content, and collecting information. Its purpose is to help search engines understand what’s on the web.


Key Points:

Indexing Content: Crawlers play a crucial role in the indexing process of search engines. They visit web pages, read the content, and store information about those pages in the search engine’s database.

Frequency of Crawling: Search engine crawlers visit websites regularly to keep their index updated. The frequency of crawling depends on various factors, including the website’s update frequency and importance.

Discovering New Pages: Crawlers follow links on web pages to discover new content. When a new page is found, it is added to the queue for crawling and indexing.

When you perform a search on a search engine, the results you see are based on the information collected by crawlers. These crawlers have visited and analyzed countless web pages to create an index that can be quickly searched to provide relevant results.

In summary, a crawler is an automated program that systematically navigates the internet, visiting web pages, and collecting information for search engines. It is a crucial component in the process of indexing and updating search engine databases, ensuring that search results are relevant and up-to-date.