C# networking refers to using the C# programming language to create networked applications. This can include server-side code to handle incoming client connections and client-side code to communicate with servers.

To get started with C# networking, it’s helpful to have a basic understanding of networking concepts such as TCP/IP, sockets, and protocols like HTTP and WebSocket. Once you have a grasp of the fundamentals, you can start exploring the various networking libraries and frameworks available for C#.

Here are a few key libraries and frameworks commonly used for C# networking:

1. Socket class: The `System.Net.Sockets.Socket` class is included in the .NET framework and provides a low-level interface for network communication using sockets. This allows you to create both server and client applications that can send and receive data over TCP/IP or UDP.

2. TcpClient and TcpListener: These classes in the `System.Net.Sockets` namespace provide an easier-to-use abstraction for TCP/IP networking. `TcpListener` allows you to create a server that listens for incoming TCP connections, while `TcpClient` allows you to create a client that can connect to a server.

3. WebClient and HttpClient: If you’re working with HTTP, you can use the `System.Net.WebClient` class or the newer `System.Net.Http.HttpClient` class to make HTTP requests to servers and retrieve the responses.

4. SignalR: SignalR is a high-level library for building real-time, web-based applications. It provides an abstraction over various transport protocols (including WebSocket) and allows for bidirectional communication between server and client. SignalR is often used for building chat applications, real-time dashboards, and collaborative tools.

5. ASP.NET Core: If you’re building web applications, you can use the ASP.NET Core framework, which includes built-in support for handling HTTP requests and responses, as well as WebSocket communication. ASP.NET Core also provides features like authentication, authorization, and dependency injection, making it a powerful option for building networked applications.

To dive deeper into C# networking, you can explore tutorials, documentation, and sample code provided by Microsoft. Additionally, there are plenty of online resources, books, and courses available that cover C# networking in more detail.