应用：单个程序内，需要执行较多的内容，且可以分成多个部分

好处： 层次分明 易于更改、调试

注意：利用自定义数据类型

执行流程控制准确

输入输出连接

延时

停止-Applications: within a single program, you need to perform more content, and can be divided into a plurality of portions

Benefits: Easy to change structured, commissioning

Note: Using Custom Data Types

                           　Accurate execution flow control

                           　Input and output connections

                           　Delay

                           　stop