A client is an application or system that accesses a service made available by a server.
Clients are generally classified as either "fat clients", "thin clients", or "hybrid clients".
Fat
A fat client, also known as a rich client or thick client, is a client that performs the bulk of any data processing operations itself, and does not necessarily rely on the server.
Thin
A thin client is a minimal sort of client. Thin clients use the resources of the host computer.
Hybrid
A hybrid client is a mixture of the above two client models. Similar to a fat client, it processes locally, but relies on the server for storage data. This approach offers features from both the fat client (multimedia support, high performance) and the thin client (high manageability, flexibility).
Disambiguation
The word client is used in several contexts within the Information Technology industry. This tag is for client as defined above. Other uses include:
- In SSL and TLS, the client is the thing that initiates the connection. While these are normally equivalent to client and server in the traditional sense, the distinction is important for establishing secure peer-to-peer connections.
- Client may refer to the line of business within the enterprise who is paying for an internal service.
- Client may refer to a 3rd party paying for the services of the company, i.e. a customer.
These ambiguities are frequently the source of misunderstandings and confusion so it is advisable to qualify the term in cases where the intended meaning might be unclear.
