A Client in computer networking refers to a computer or an application that requests and retrieves information from a Server.

At its core, a server provides a service to other computers or devices. The service is provided through the Internet or a local network. The two most popular types of services that a server can render are the storage and retrieval of files or data and the processing of information on behalf of the client. A single server can service multiple clients at the same time and a single client is able to access multiple servers simultaneously.

A server works by listening for requests from a client. When a request is received, it is processed and some sort of response is sent back. This response can be the requested information, a simple message saying that the request was received and processed successfully, or even just an HTTP status code like 200 (OK).

The types of requests a server can recognize depend solely on the number of server applications that are installed and active on the machine. The more server software packages there are, the more capable the server becomes in terms of what it can do. But if you install too many software packages, you run the risk of overloading the server and causing it to freeze. As such, server administrators perform a balancing act between how capable a server is set up to be and how many requests it can handle at the same time.