Windows Sockets API (Winsock)

Windows Sockets API (Winsock) is an application programming interface (API) designed for communication between network-connected software on Windows operating systems. It was introduced in 1992 to streamline the development of networking software for Microsoft Windows, and supplanted the older networks such as NetBIOS and NetBEUI. It was the basis of the Windows Internet Architecture and made TCP/IP a core part of the Windows operating system.

An important feature of Winsock is its ability to provide an abstraction layer between applications and the TCP/IP stack, meaning that applications can access the network without having to be tied to the specifics of the underlying protocol, making them both more reliable and more portable. This allows for the development of cross-platform protocol implementations, for example with the use of cross-platform open source libraries.

Although Winsock remains a popular way of producing higher-level networking applications on Windows, more recent versions of Windows offer Windows Sockets 2, which is a more modern version of the API, offering higher performance and more compatibility with non-Windows operating systems. It is a more robust and efficient implementation compared to winsock and takes better advantage of the advances in network technology.

Winsock is used to connect different type of applications, for example a web browser, to a remote server computer. It is used for transferring data in a variety of protocols and provides access to lower-level network operations such as network address resolution. It also provides a platform for developing other applications such as mail servers and game servers.