Crawl is the process by which search engine bots discover and fetch web pages and resources.
It matters because organic search compounds over time when pages are technically accessible, useful, differentiated, and connected to real search intent. Clear SEO terminology also helps teams avoid shortcuts that create long-term risk.
Example
A crawler follows a link from a category page to a new article and requests its URL. That fetch is crawling; whether the article is indexed or shown for a particular search involves additional processing and decisions.