PHP Syntax

PHP is executed on the server, and the HTML result is sent to the browser.

Basic PHP Syntax
A PHP scripting block always starts with <?php and ends with ?>. A PHP scripting block can be placed anywhere in the document. 

 <html><body>
 <?php

 ?>
 </body></html>

A PHP file normally contains HTML tags, just like an HTML file, and some PHP scripting code. Below, we have an example of a simple PHP script which sends the text “Hello, World!” to the browser: 

 <html><body>
 <?php
  echo "";
 ?>
 </body></html>

Each code line in PHP must end with a semicolon. The semicolon is a separator and is used to distinguish one set of instructions from another. There are two basic statements to output text with PHP: echo and print.

Comments in PHP
// is for a single-line comment and /* and */ are for a large comment block. 

 <html><body>
 <?php
   // This is a comment
   /* This is
      a comment block */
 ?>
 </body></html>