One minute to figure out what are predefined variables in php? What is the $_POST variable?

We have learned so much about PHP. Today we will learn in one minute what are predefined variables in PHP? What is the $_POST variable? , I wonder if you have fully mastered it. If not, then follow this article to continue learning

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Predefined variables:

The so-called predefined variables actually refer to variables that are predefined in the language tool PHP;

We just "enjoy it and use it"

Overview:

Mainly include:$, _GET,S_ POST,$_ REQUEST, $ _ SERVER, $GLOBALS,

• ## are all arrays

• system definition and maintenance - that is, we should not assign values ​​​​to them or To destroy its value, you should only "use its value"

• has a super-global scope and can be used anywhere.

• May have different values ​​in different situations

$_POST variable:

Meaning:

It represents all the data submitted when the user submits through the form in post mode (methodu "post") - this is called post data.