Predefined /home/cwmeyers/public_html/week3/predefined.php

Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)

Apache

Predefined variables are variables within PHP code that have their own values prior to the code being processed. These predefined variables usually contain information regarding the server as a whole, such as operating system, or file name. Some examples of predefined variables are: $_SERVER['SCRIPT_FILENAME'], $_SERVER['HTTP_USER_AGENT'], and $_SERVER['SERVER_SOFTWARE']. These predefined variables are used to determine the current files name, the user agent, and the operating software respectively.

/home/cwmeyers/public_html/week3/predefined.php

Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)

Apache

These predefined variables often have long names but these can be shortened simply by creating standard variables with the stored definition of the predefined variable to make them easier to recall within the code. An example of this process is as follows: $file = $_SERVER['SCRIPT_FILENAME']. In this example we take the predefined variable I mentioned above, $_SERVER['SCRIPT_FILENAME'], and equate it to the much shorter variable of $file, thus making it much easier to recall in later code.

Now, instead of having to type out the entirety of $_SERVER['SCRIPT_FILENAME'] in order to call it to action in my code, I can simply type $file and it will run the predefined variable instead.