Before starting the installation, first you need to know what do you
want to use PHP for. There are three main fields you
can use PHP, as described in the
What can PHP do?
For the first and most common form, you need three things:
PHP itself, a web server and a web browser. You
probably already have a web browser, and depending on
your operating system setup, you may also have a web
server (e.g. Apache on Linux and MacOS X; IIS on Windows).
You may also rent webspace at a company. This way, you
don't need to set up anything on your own, only write
your PHP scripts, upload it to the server you rent, and
see the results in your browser.
In case of setting up the server and PHP on your own, you have
two choices for the method of connecting PHP to the
server. For many servers PHP has a direct module
interface (also called SAPI). These servers include
Apache, Microsoft Internet Information Server,
Netscape and iPlanet servers. Many other servers
have support for ISAPI, the Microsoft module
interface (OmniHTTPd for example). If PHP has no
module support for your web server, you can always
use it as a CGI or FastCGI processor. This means you set up
your server to use the CGI executable of
PHP to process all PHP file requests on the server.
If you are also interested to use PHP for command line
scripting (e.g. write scripts autogenerating some images
for you offline, or processing text files depending
on some arguments you pass to them), you always need
the command line executable. For more information, read
the section about writing
command line PHP applications. In this case,
you need no server and no browser.
With PHP you can also write desktop GUI applications
using the PHP-GTK extension. This is a completely
different approach than writing web pages, as you
do not output any HTML, but manage windows and objects
within them. For more information about PHP-GTK, please
visit the site dedicated to
this extension. PHP-GTK is not included in the
official PHP distribution.
From now on, this section deals with setting up PHP
for web servers on Unix and Windows with server module
interfaces and CGI executables. You will also find
information on the command line executable in the
PHP source code and binary distributions for Windows can be
We recommend you to choose a
to you for downloading the distributions.