NetworkStream is a class in the System.Net.Sockets namespace of the Microsoft .NET Framework. It provides a way to send and receive data over a network connection using streams. This class is typically used with TcpClient or TcpListener to facilitate communication between a client and a server. With NetworkStream, developers can read and write data in a continuous flow, making it suitable for applications that require real-time data transfer, such as chat applications or online gaming. It supports both synchronous and asynchronous operations, allowing for efficient handling of network data without blocking the main application thread.