PHP Introduction

What is PHP?

PHP is a Hypertext Preprocessor, php is a server "side" scripting like ASP.
PHP script are executed on the server.
PHP support many database :

MySql
Informix
Oracle
Sybase
Solid
PostgreSQL
Generic ODBC, ect.

PHP is an open source software, php is free to download and use.

What is PHP file?

PHP file can contain text, HTML tags and script.
PHP files are returned to the browser as plain HTML.
PHP files have a file extension of :

php
php3
phmtl

Where to start this function?

Install Apache (IIS) on your own server, then Install PHP and MySql or find a web hosting plan with php and MySql support.

What I need to running PHP?

If your server support PHP you aren't need anything. Just create some *.php files in your web directory and server will parse them for you. Because it's free, most web hosting offer php support for your php plan.
Below is a link to a good tutorial from php.net on how to install.

Nyut'z