An XML sitemap is a file that lists all the important pages on your website, helping search engines discover and crawl them more efficiently — especially useful for large or newer websites. The robots.txt file tells search engine crawlers which pages or sections of your site they should or shouldn’t access. Crawl errors occur when Google tries to access a page but fails — due to broken links, server errors, or blocked pages — and these are visible in Google Search Console under the “Coverage” or “Pages” report. Regularly checking and fixing crawl errors ensures all your important pages remain indexed and eligible to rank.