What Does Client Mean?

A client is the receiving end of a service or the requestor of a service in a client/server model type of system. The client is most often located on another system or computer, which can be accessed via a network. This term was first used for devices that could not run their own programs, and were connected to remote computers that could via a network. These were called dumb terminals and they were served by time-sharing mainframe computers.


Techopedia Explains Client

A client can be a simple application or a whole system that accesses services being provided by a server. A client can connect to a server through different means like domain sockets, named, shared memory or through Internet protocols, which is the most common method being used since the wide adoption of the Internet.

Clients are classified into three types:

  • Thin Client: A client application with minimum functions that uses the resources provided by a host computer and its job is usually just to display results processed by a server. It simply relies on a server to do most or all of its processing.
  • Thick/Fat Client: This is the opposite of the thin client. It can do most of its processing and does not necessarily rely on a central server, but may need to connect to one for some information, uploading, or to update data or the program itself. Anti-virus software belong to this category because they do not really need to connect to a server to do their job, although they must connect periodically to download new virus definitions and upload data.
  • Hybrid: Exhibits characteristics from the two above types. It can do most processes on its own but may rely on a server for critical data or for storage.

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Margaret Rouse

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.