PHP Syntax & Hello World Example

Syntax

PHP Script can be placed any where in the document. and it start's with <?php and ends with ?>


<?php

//php Code goes here

?>
				

By Default php file Extension is .php but you can also override the extension in your web server settings to your required extension.

Hello World Example

PHP document contains html, Java-Script, Css or any other front end scripting language.

in below example we will use the php code in the body of html. echo is used to print data.

<!doctype html>	
<html>
	<head>
		PHP Hello World Example
	</head>
	<body>
	<?php
		echo 'Hello World';
	?>
	</body>
</html>

Comments

Comment is very important ingredient in every programming language. PHP Provide Single line comments and also multi line comments option.

<!doctype html>	
<html>
	<head>
		PHP Hello World Example
	</head>
	<body>
	<?php
	
		//This is a single line comment.
		
		#This is another way of writing single line comment.
		
		/*
		 *This is a 
		 *Multi line 
		 *Comment
		 */
		 
		 $value=10; //you can also comment like that.
		 $total=$value/*here you can also place the comment*/+20;
	?>
	</body>
</html>

PHP Rules

  • PHP Syntax based on C
  • PHP Every line terminates with semi colon (;)
  • PHP Keywords like (e.g if-else,for, echo, etc.), classes, functions and user-defined functions are not case sensitive.
  • PHP Variables are case sensitive