Focused crawls are collections of frequently-updated webcrawl data from narrow (as opposed to broad or wide) web crawls, often focused on a single domain or subdomain.
The Wayback Machine - https://web.archive.org/web/20190611102902/https://apps.apple.com/cn/app/%E6%8A%96%E9%9F%B3%E7%9F%AD%E8%A7%86%E9%A2%91/id1142110895