can anybody explain me about PHP? What is the expansion of PHP

PHP is a simple scripting language to create web pages dynamically (usually).

It can be installed on any popular Operating System/platform including Windows.

You can also write simple programs, and run them via the command line on your local PC.

I don't know what you mean by "what is the expansion of PHP".

You can visit the official PHP web site here: www.php.net, or you can visit the documentation directly at http://www.php.net/manual/en/.

An other great place to learn about PHP is www.w3schools.com. You can learn much about the basics through their tutorials.