This chapter will go through a simple PHP program and show you basic PHP syntax.
Let’s create a hello world PHP program, and display the output in the command line and in browser.
Create a new file called hello.php with the following contents:
<?php
echo 'Hello world';
And run it in the command line with:
php hello.php
You should see output similar to this:
Hello world
First line in above file is a so called opening PHP tag - <?php. PHP code
needs to be wrapped in PHP tags for PHP to be able to parse it. You can also
embed the PHP code directly in the HTML file. For example, let’s create a file
php-and-html.php:
<html>
<body>
<?php echo 'Hello world'; ?>
<body>
</html>
<?php?>And display it in the browser:
php -S localhost:8000 php-and-html.php
Now, visit URL http://localhost:8000 in your favourite browser, and you should
see output of Hello world.
Comments in code are language elements that indicate which parts of the code should not be parsed and processed. PHP provides two types of comments:
<?php
// This is a single line comment.
echo 'Hello world';
And multiline comments:
<?php
/*
This is multiline comment.
*/
echo 'Hello world';
Expressions are basic building block of any language, including PHP.
After the introduction chapters, it is time to learn something more about PHP language syntax. Proceed to the next PHP language reference chapter.
