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fat client - Computer Definition
In contrast to a thin client, a fat client possesses considerable resources (e.g., memory, hard drive storage, and processing power) and functionality independent of a server. See also client, client/server, server, and thin client.
A user's computer that contains its own applications that are run in the machine. New programs are installed on the local hard disk. This is the typical way people use their computers. Contrast with thin client and fat server. See two-tier client/server.
A Fat Client
A client with a healthy appetite for processing. (Image courtesy of Originetics, Inc.)