Thick Client

A thick client (also called a heavy client) is a fully-functional computer that performs most processing locally rather than relying on a server. Unlike a thin client, a thick client includes its own operating system, storage, and applications, allowing it to operate independently — even when not connected to a network.

While a thick client can function offline, it is still considered a "client" when connected to a server or network. Clients may access shared resources such as files, databases, authentication services, or centrally-managed applications. However, the core software and computing power reside on the local machine rather than the server.

Thick clients are commonly used in business and professional environments where performance, offline access, or specialized software is required. Examples include desktop PCs and laptops that run locally installed applications like design software or productivity suites. A thick client used for a specialized purpose is also called a workstation.