freeCodeCamp/guide/english/php/php-syntax/index.md

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---
title: PHP Syntax
---
# Basic PHP Syntax
### Start
All PHP files are saved by the extension ` .php `. PHP scripts can be added anywhere in the document. A PHP script starts with ` <?php ` and ends with ` ?> `.
` <?php //PHP code goes here ?> `
### Print
To print any statement in PHP we use `echo` command.
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#### Code sample
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```php
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<!DOCTYPE html>
<html>
<body>
<h1>My first PHP page</h1>
<?php
echo "Hello World!";
?>
</body>
</html>
```
##### NOTE: PHP statements ends with semicolon `;`
### Declaring Variables
We declare variables in PHP by adding dollar `$` sign before them.
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```php
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<?php
$x = 5;
echo $x;
?>
```
### Comments in PHP
To write a single line comment in PHP we put hashtag `#` or by putting `//` before the comment.
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```php
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<?php
# This is a single line comment
// This is also a single line comment
?>
```
To write a multiple line comment we start the comment with `/*` and end with `*/`.
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```php
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<?php
/* This is a
Multiple line comment. */
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?>
```
We can also comment out some parts of the code line.
#### Code Sample
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```php
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<!DOCTYPE html>
<html>
<body>
<?php
// You can also use comments to leave out parts of a code line
$x = 5 /* + 15 */ + 5;
echo $x;
?>
</body>
</html>
```
You can see more about this on [PHP Manual](http://php.net/manual/en/)