C# async/await

using System;
using System.Diagnostics;
using System.Net;
using System.Threading;
using System.Threading.Tasks;

namespace TestAcync
{
    class Program
    {
        class Foo
        {
            public async void Do()
            {
                Console.WriteLine("Enter your name: ");

                string name = Console.ReadLine();

                Stopwatch sw = Stopwatch.StartNew();

                string s = await AsyncHello(name);

                sw.Stop();

                Console.WriteLine(string.Format("{0}, Ellapsed {1} ms", s, sw.ElapsedMilliseconds));

                Console.ReadKey();
            }

            public Task<string> AsyncHello(string name)
            {
                var task = new Task<string>(() =>
                {
                    Thread.Sleep(5000);

                    return string.Format("Hi, {0}", name);
                });

                task.Start();

                return task;
            }
        }

        static void Main(string[] args)
        {
            var foo = new Foo();

            foo.Do();

            Console.ReadKey();
        }
    }
}