start php

As we start any language from run "Hello World"
save you page with the extension name .php the page of hello world is sample and shown below
there are starting and ending tags of php which are <?php     ?>
we write every code in these tages
for example
<?php

echo"hello world";

?>
 the output will be
hello world
how to use HTML tags in php
we simply write the html tags in the "" of echo.
      ie: 
<?php


echo"<h1>Hello World</h1>";


?>
what will be the output of this code:

Hello World