Hello, I've been reading up on async/await somewhat but there are still things I don't get. I have experience writing socket servers with the Begin/End pattern, but I find some of this async/await ...

Dave Marini delves into the history of asynchronous programming on the .NET platform, tracing through the early days of the Asynchronous Programming Model to today’s async/await patterns.

Hence, you can take advantage of async and await to implement asynchronous file operations when working with .Net Framework 4.5 or later. You can learn more about async and await on MSDN.

Asynchronous services are easier to implement with support of the await and async keywords in WCF 4.5. We look at that, as well as contract-first development.

Exception handling is different for asynchronous code. Learn the exception handling semantics for asynchronous methods in C#.

However in the example I gave, the async void HandleClient method, there is an await SslStream.ReadAsync (...) call done immediately, which is an async I/O operation that will not consume a thread ...