What is written on the left is correct, but what was edited and submitted on the right is wrong and misled me for a long time
The truth will be revealed with pictures
The version of his online editor is php7. The way of defining global variables in the global way seems to have been abolished in php7. It is recommended to use $_GLOBAL directly, which is the officially recommended way
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
The version of his online editor is php7. The way of defining global variables in the global way seems to have been abolished in php7. It is recommended to use $_GLOBAL directly, which is the officially recommended way