C# 中的 break 和 continue 语句有什么区别？

using System;
namespace Demo {
   class Program {
      static void Main(string[] args) {

         /* local variable definition */
         int a = 10;

         /* loop execution */
         while (a > 20) {
            if (a == 15) {
               /* skip the iteration */
               a = a + 1;
               continue;
            }
            Console.WriteLine("value of a: {0}", a);
            a++;
         }
         Console.ReadLine();
      }
   }
}

using System;
namespace Demo {
   class Program {
      static void Main(string[] args) {
         /* local variable definition */
         int a = 10;

         /* while loop execution */
         while (a < 20) {
            Console.WriteLine("value of a: {0}", a);
            a++;

            if (a > 15) {
               /* terminate the loop using break statement */
               break;
            }
         }
         Console.ReadLine();
      }
   }
}