What Youll Need
The most important requirement for working with PHP--since it is a server-side scripting language--is access to a PHP-enabled server. Considering PHPs popularity, your ISP or Web host most likely provides this option. (To be sure, contact them to see what technology they support.) As of this writing, 1,000 ISPs and Web hosts offer PHP.
The other option is to install PHP on your own server--commonly just a machine running Windows NT or Linux and the necessary Web-server application. (For example, Apache is a free Web-serving application for Linux; you could use Personal Web Sharing with Windows, or IIS with Windows 2000.) Installing PHP is really straightforward, and there is ample help available online. If you are up to the task of building your own PHP-installed server, PHP is available for free from the PHP Web site, and you can download Apache from the http://httpd.apache.org.
The second requirement is almost a given: that you have some sort of text editor on your computer. Notepad, WordPad, SimpleText, and similar freeware applications are all sufficient for your purposes, although BBEdit, WordPerfect, Word, and other commercial programs offer features that you may appreciate. If you are accustomed to using graphical interface (also referred to as WYSIWYG--What You See Is What You Get) editors like Dreamweaver or GoLive, consult your manual to see how to program PHP with them.
Third, you need some method of getting the scripts you write in your text editor to the server. If you are working directly on your own server, you can simply save the scripts to the appropriate directory. However, if you are using a remote server owned by your ISP or Web host, you will need an FTP (File Transfer Protocol) program to send the script to their computer. Another option is to telnet to the remote server and use an editor such as vi or pico to write your scripts directly on that machine.
What Are You Waiting For?
I hope that this quick introduction to PHP has whet your appetite for building dynamic Web applications. With just a little HTML experience and a copy of like PHP for the World Wide Web: Visual QuickStart Guide, you will be creating exciting Web sites in no time!