13. A system for managing online user profiles, the system comprising: a processor system configured to: fetch, over an electronic network, textual data associated with a plurality of URLs, the fetching being performed according to a prioritization sequence based on impression counts, such that URLs with higher impression counts have their textual content fetched before URLs with lower impression counts; generate, and store in a database system, one or more keywords in relation to each of the URLs, based on respective textual content fetched for each of the URLs; receive information about online activity of a user, the information including at least a unique user ID and a URL requested by the user; search the database for one or more keywords stored in relation to the requested URL; and generate or update a user profile of the user to include the one or more keywords stored in relation to the requested URL; and a database system configured to store one or more of the information, the textual content, the keywords, and the user profile.
19. The system of claim 13 , wherein the system further includes a user interface.