什么是委托以及案例

using System;
using System.Collections.Generic;
using System.Text;
namespace Delegate
{
//定义委托，它定义了可以代表的方法的类型
public delegate void GreetingDelegate(string name);
class Program
{
private static void EnglishGreeting(string name)
{
Console.WriteLine("Morning, " + name);
}
private static void ChineseGreeting(string name)
{
Console.WriteLine("早上好, " + name);
}
//注意此方法，它接受一个GreetingDelegate类型的参数，该参数是返回值为空，参数为string类型的方法
private static void GreetPeople(string name, GreetingDelegate MakeGreeting)
{
MakeGreeting(name);
}
static void Main(string[] args)
{
GreetPeople("Jimmy Zhang", EnglishGreeting);
GreetPeople("张子阳", ChineseGreeting);
Console.ReadKey();
}
}
}