When starting to learn a new programming language the most basic is to write a "Hello World" program. The essence is to write a program that starts, prints something to the screen and ends correctly. Hello World programs have been the de facto basic program for beginners and test purposes after the first Hello World program was published by Kernighan and Ritchie in the classic text book on C "The C Programming Language". Hello World programs in more than 600 different programming languages can be found at The Hello World Collection
Hello World in PHP
<?php
echo "Hello World!";
?>
<?php is the start of a PHP code block. echo is a standard PHP funtions that prints a string. ?> ends the PHP code block. An entire file can be a code block or a file can contain many code blocks. For example, a file can be a mix of HTML, JavaScript, CSS, and PHP.