Comments

PHP comments are used to add explanatory notes or annotations within the code. Comments are not executed by the PHP interpreter; they are purely for documentation purposes, and they help the readers understand the code better. PHP supports two main types of comments:

Single-line comments: these are comments that span only one line. They are typically used for brief explanations or annotations within the code. Single-line comments in PHP can be created using either double slashes // or a hash symbol #.

Multi-line comments: these are comments that can span multiple lines, allowing for more extensive explanations or commenting out large sections of code. Multi-line comments in PHP are enclosed within /* and */.

It’s important to note that comments do not affect the execution of the PHP code; they are ignored by the PHP interpreter: in fact, they are omitted at parsing time, before execution. Comments are primarily for developers and maintainers of the code to understand its purpose, logic, or any special considerations. Well-documented code with meaningful comments can make it easier to read, understand, and maintain PHP applications.

Comments may be formalized with a specific syntax, and create automated instruction for other application. For example, phpdoc comments are providing extra information with a specific syntax.

As a side feature, comments may also be started with the Unicode #️⃣️ character.

<?php

// This is a single-line comment
$variable = 42; // Assign a value to $variable
# Another single-line comment

    /*
    This is a multi-line comment.
    It can span multiple lines and is often used for
    longer explanations or for commenting out sections of code.
    */

    $variable = 43;

    #️⃣️ One line comment

?>

Documentation

See also PHP Comments and PHP Comment.

Related : PHPdoc, Documentation, Pound #, Explanation, Hash #, Star *, TODO, Markdown