Overview

PHP (acronym for Hypertext preprocessor) is probably the most popular scripting language of the web. It is used to enhance web pages.

Web Architecture

1. The user access the website through the browser.
2. The page is requested by the browser from the web server.
3. Web server will collect the requested page( html,images and all etc.) from its document root.
4. If it is a static element e.g html, css or JavaScript the response is returned directly to the browser and the browser renders it to User screen.
5. Else if it is a PHP file the web server sends it content to the PHP interpreter which interpret and executes the code in the file. It also performs Database operation if required.
6. PHP interpreter then generates output( if required) and sends it to the web server.
7. Web server then sends the same to the browser which renders it to the User screen.

Origin of PHP

It was created in 1944 by Rasmus Lerdorf for the purpose of tracking visits to his online resume, the collection of which he named Personal Home Page Tools.Its first incarnation was written in C programming language
Over time more functionality was required which brought us to this present stage.

Why Use PHP

Open Source
Free Download and Usage
Wider Community of users
Efficient running on the server

PHP Strengths

Compared to Its contemporaries, PHP is easier to learn, more popular and has a wider audience than others.

PHP Contemporaries

PHP is not the only scripting language that accesses database or the web server others include Perl, Java Server Page and Microsoft Asp.net to mention a few each of which has its own strength and weaknesses.

Availability

PHP is available on multiple platforms e.g Windows, Linux, Unix, Mac OS etc.
It is also compatible with almost all web server in use today e.g Apache and IIS.

Installing PHP as a module for Apache

There are quite a few of softwares that come with PHP packages e.g Xampp Server and Wamp . It is advisable to check them all out to see what each has to offer before making your choice.