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/20120609232440/http://www.sfgate.com/cgi-bin/contribute/sn/gallery?plckGalleryID=c9217a4f-1fa9-4c76-a434-9b361831f425
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