A crawler, also known as a web crawler or spider, is an automated programme used by search engines to systematically browse the internet and index content from websites. Crawlers operate by following links on webpages to discover new pages and gather information about them, including text, images, metadata, and other relevant data. This process is essential for search engines like Google, Bing, and others to build their databases of web content.
When a user enters a query into a search engine, the indexed information allows the engine to quickly retrieve and rank results based on relevance and quality. Crawlers adhere to specific protocols such as the Robots.txt file found on websites; this file instructs crawlers which parts of a site should be accessed or ignored.
The efficiency of crawling impacts SEO significantly. Websites that are well-structured with clear navigation tend to be more easily crawled than those that are poorly organised or have broken links. Additionally, regular updates to a websites content can encourage more frequent crawling by search engines.
