Intro to PHP

In this article we'll introduce you to one of the Internet's hottest and fastest growing server side programming languages, PHP. PHP (or Personal HomePage Tools) was created by Rasmus Lerdorf over three years ago to track visitors to his homepage. PHP has since evolved into a powerful server-side markup language with syntax that resembles a mix between Perl and C.

Why Use PHP

Most Web developers know that Web pages are more than pretty pictures and text; these days, even the most amateur of sites strive to have some sort of animation or interactivity. Most of the higher end sites have features such as discussion forums, search engines and/or shopping carts. PHP enables you to add features quickly.

The old fashioned approach to adding interactivity was to use CGI scripts in Perl. The problem is that CGI is not very scalable; each new request to a CGI script requires the server to start a new process in the kernel, which uses both CPU time and memory, making CGI scripts much slower which in turn make multiple concurrent CGI scripts run very slowly. PHP solves this problem by becoming a part of the Web server itself, saving the end user a considerable amount of load time.

Another reason to use PHP is because it's free. That's right, PHP is an open source project, meaning that any user can download both the source code and executables for PHP and install them on their computer for free. Because PHP is open source, it is solid and is constantly being improved by many experienced programmers. It is currently available for all major platforms.

Finally, PHP is easy. If you know C or Perl, learning PHP is a cinch. The language is a mix between the two, taking the best features from both. Plus PHP adds features to solve common problems that programmers often encounter when programming for the Web. For example, you can embed PHP code directly into an HTML file, whereas in Perl and C you would have to use additional print statements to output HTML. Another advantage to PHP is its native database support for 12 databases (including mSQL and mySQL), which allows access to the databases directly through SQL statements. And if you don't know either of these programming languages, then PHP is an excellent gateway into the world of programming.

Next: More About PHP

This article originally appeared in the October 28, 1999 edition of the WebReference Update Newsletter.