What are Register Global Variables?
 

It is a frequent necessity to transfer variable values between pages. You may have an HTML

which asks for user input to named fields. These fields (as well as hidden variables) will be transferred to a PHP page for processing. This may be the same page that defines the form, or a different one. A method of either 'post' or 'get' must be given in the form tag.

Another way to transfer variable data to another page is make an HTML link (such as with click this link).This of course can be entered on the browser's address line, too. This information (the stuff after the ?, or "var_name_1=data&var_name_2=data") is known as a URL Query String ("UQS") and can be treated like a "GET" form submission.

Register globals variables is convenient but extremely dangerous, allows an attacker to overwrite variables in a script by adding parameters to requests. While the feature has been disabled by default since PHP 4.2.0. Many hosting providers often enable the feature to provide compatibility with old scripts.

What are Register Global Variables?
 

It is a way to transfer variable data to another page is make an HTML link (such as with click this link).This of course can be entered on the browser's address line, too. This information (the stuff after the ?, or "var_name_1=data&var_name_2=data") is known as a URL Query String ("UQS") and can be treated like a "GET" form submission.
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