The Web is more than just text. Images appear in the form of logos, buttons, photographs, charts, advertisements, and icons. Many of these images are static and never change, built with tools such as Photoshop. But many are dynamically created—from advertisements for Amazon’s referral program that include your name to graphs of stock performance.
PHP supports graphics creation with the built-in GD extension. In this chapter, we’ll show you how to generate images dynamically with PHP.