Definition
A web crawler, also called a spider or bot, is a program that visits web pages, downloads their content and follows links to find more pages. Search engines use crawlers to build their indexes, and AI companies use them to collect training data or to find pages for search features. Crawlers identify themselves with user-agent names.
For example, Googlebot might discover a new Aarvi Skin product page by following a link from the homepage, then return later to check for changes. A page with no internal links and no sitemap entry may never be found at all.
Why it matters
Crawling is the discovery layer for search engines and many AI systems. If a crawler cannot reach a page, it cannot be indexed, retrieved or cited, whatever its quality. Understanding how crawlers find pages, through links, sitemaps and direct requests, helps you make sure your most important content is reachable. It also helps you interpret server logs and decide which crawlers to allow.
What to do
- Link important pages from your navigation or from other well-linked pages.
- Keep XML sitemaps current and submit them in Search Console and Bing Webmaster Tools.
- Review server logs to confirm major crawlers reach your key pages without errors.
Common questions
What is the difference between a web crawler and an AI crawler?
An AI crawler is a type of web crawler operated by an AI company. General web crawlers, such as search engine bots, build search indexes. AI crawlers may collect training data, support AI search features or fetch pages on behalf of users. Both follow similar technical rules.
How often do crawlers visit a website?
It varies by crawler and site. Frequently updated, well-linked sites tend to be crawled more often. Server capacity, errors and crawl rules also affect frequency. Your server logs show the actual pattern for your site, which is more reliable than general estimates.