PHP (PHP - Hypertext Preprocessor) is powerful HTML-embedded scripting language  originally designed for producing dynamic webpages.The goal of the language is to allow web developers to quickly write dynamically generated pages.

When someone visits your PHP webpage, your web server processes the PHP code. It then sees which parts it needs to show to visitors(content and pictures) and hides the other stuff(file operations, math calculations, etc.) then translates your PHP into HTML. After the translation into HTML, it sends the webpage to your visitor's web browser.

You may be wondering why you should choose PHP over other languages such as Perl or even why you should learn a scripting language at all. I will deal with learning scripting languages first. Learning a scripting language, or even understanding one, can open up huge new possibilities for your website. Although you can download pre-made scripts from sites like Hotscripts, these will often contain advertising for the author or will not do exactly what you want. With an understanding of a scripting language you can easily edit these scripts to do what you want, or even create your own scripts.

Using scripts on your website allows you to add many new 'interactive' features like feedback forms, guestbooks, message boards, counters and even more advanced features like portal systems, content management, advertising managers etc. With these sort of things on your website you will find that it gives a more professional image. As well as this, anyone wanting to work in the site development industry will find that it is much easier to get a job if they know a scripting language.

What you should already know

Before you continue you should have a basic understanding of the following:

HTML / XHTML

Some scripting knowledge

Where to Start?

• Install an Apache server on a Windows or Linux machine

• Install PHP on a Windows or Linux machine

• Install MySQL on a Windows or Linux machine 

Credits: www.freewebmasterhelp.com, www.w3schools.com  

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