Asynchronous programming using async and await the

　　Asynchronous Programming Model (TAP) provides an abstraction of asynchronous code. Asynchronous code looks no big difference synchronization code, nothing more than two keywords (async and await). However, the order of execution of the code did not look so simple, different and change the order of execution of code to complete the task and cpu resources according to changes in time. This is similar to the same people with different instructions for the process tasks include asynchronous operation.