The ability to include the contents of one file inside another is one of the most powerful features of PHP. It’s also one of the easiest to implement. This means code can be incorporated into multiple pages—for example, common elements, such as a header, footer, or navigation menu. PHP merges the content into each page on the server, allowing you to update a menu or other common elements by editing and uploading a single file—a great timesaver.
As you work through this chapter, you’ll learn how PHP includes work, where ...