After briefly explaining what PHP is and how it integrates with HTML, David introduces the features of the language. He covers variables, conditional statements, calculations, loops, and functions, as well as server-side includes and error handing, in a series of hands-on exercises. He then moves to a larger project that involves building a script to validate and email user input from an online form. By following along, you'll come to understand the value of creating reusable code, the importance of PHP security, and how to deal with multiple-choice form fields.

Topics include:

• Naming variables
• Storing text as strings
• Doing calculations with PHP
• Using conditional statements to make decisions
• Creating custom functions
• Deciphering error messages
• Emailing the contents of an online form
• Dealing with multiple-choice form fields