We also assume you can program in a third-generation programming language such as C, C++, Java, Perl, FORTRAN, or Visual Basic. Our introduction to the PHP web scripting language doesn't assume you are familiar with web scripting or are an expert programmer, but we do assume you understand the basic HTML constructs and are familiar with the popular web browsers. If you can author an HTML document with a text editor that contains a <form> and a <table> element, you have sufficient HTML skills to use this book. It is the principles of structure in the markup process that are important, not the attractiveness or usability of the presentation in the web browser. We introduce advanced HTML concepts as required, but an HTML guide such as O'Reilly's HTML and XHTML: The Definitive Guide, by Chuck Musciano and William Kennedy, is a useful resource for understanding and building web database applications. You may also find O'Reilly's Programming PHP, by Rasmus Lerdorf and Kevin Tatroe useful as well.

You don't need a detailed understanding of relational databases to use this book, but a working knowledge is helpful. We present the relational database theory needed for developing simple applications, and we cover many other basic concepts, including how to tell when a database is the method of choice to store data, the architecture of a DBMS, the database query language SQL, and a case study that models system requirements and converts the model to a database design. This book isn't a substitute for the many good resources on database theory, however, it's enough to begin developing the underlying databases for many web database applications.