Learn the Basics of PHP

<?php

PHP is a popular programming language that is especially used for web development.

In this tutorial you learn the basic concepts of the PHP language and its terminology. It's assumed the reader has little to no knowledge of PHP (or other programming languages). This tutorial can be used as a starting point for people just starting with programming. The chapters are kept small and to the point for this reason.

Note: This is not a tutorial that will help you set up your website. The only aim is to give you a better understanding of the language.

It's recommended you go through the chapters in sequence. Each chapter uses information mentioned in the former chapters.

Introduction
Variables
Strings
Arrays
Loops
Functions

Introduction

PHP files are nothing more than simple text files with the file extension .php. When PHP reads a PHP file, it searches for opening and closing PHP tags <?php and ?>. This tells PHP the text inside the tags is actual PHP code. The great thing about PHP files is that they can contain HTML (and other programming languages) as well.

Here is an example of the contents of a PHP file for a web page.

<!DOCTYPE html>
<html>
    <head>
        <title>My first web page</title>
    </head>
    <body>
        <p><?php echo 'Welcome to my web page'; ?></p>
    </body>
</html>

As you can see, it contains PHP and HTML code. the PHP code started and ended with the opening and closing PHP tags <?php and ?>. If the file only contains PHP code you can just use the opening <?php PHP tag at the top of the file and leave the closing PHP tag ?> altogether.

Note: PHP requires a semicolon (;) at the end of each PHP statement. If it's missing PHP will display an error. It also stops with processing the rest of the code in the file. You can see an ending semicolon in the code above.

Errors are bound to happen, even to the most experienced developers. Don't worry about it. In this tutorial many common errors are explained.

To recap:

PHP files have a .php file extension
PHP files can contain PHP and HTML
PHP code needs to be inside opening and closing PHP tags.
You only need the opening PHP tag if the file contains only PHP code
A semicolon is needed after each PHP statement
PHP stops working if there's an error
Errors are bound to happen

Editing PHP Files

(Todo)

Next chapter: Variables

keesiemeijer/php-basics-tutorial

Learn the Basics of PHP

Introduction

Editing PHP Files