Sometimes you have to write a comment in the code to someone else or even for himself. Then you can use one of several methods for the determination by which the PHP parser will know that the text is not part of the script and can be ignored. The following methods are used to indicate that the text of the site by the end of the line is a comment:

Example
<? php

echo “text code”;                                 // This method is known for C / C ++

echo “text code”;                              # And this from a Unix shells

?>