This book is designed to be used with Linux machines, although much of the information in this book can be applied to Windows users as well. You will need PHP, MySQL, and Apache to do the exercises in this book. All three are Open Source programs, so you can download and use them free of charge. You will also need a text editor to enter your code. Finally, you’ll need a web browser, such as Internet Explorer, Netscape Navigator, Firefox, Safari, or Opera, to view your web pages.