PHP Basics

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PHP is a server side scripting language, which is run on the server before the page is served to the client. Essentially it dynamically creates pages on the fly. It can be written on it's own our within normal standard HTML etc. It must be stored on a running webserver and you can only access it via it's URL in a browser. The page the client will receive will have all of the server side elements replaced with the output of the code. If your viewed source you would only see standard HTML and text.

PHP Tags

PHP code must be contained within PHP tags, these tags can be placed anywhere in the page because they are all run before the page is served to the client.

1 <?php // the opening PHP tag
2 // your PHP code
3 ?> // the closing PHP tag

Within your PHP tags every line must be terminated with a semi colon.

Creating a Hello World in PHP

1 <?php echo "hello world"; ?>
2 //Output:
3 //hello world

echo is used to write text to the page, you could also echo html code or variables:

1 <?php echo "<p>Hello World<br>Hola Mundo</p>"; ?>
2 //Output:
3 //Hello World
4 //Hola Mundo