Many of you who are webdeveloper are planning to learn server side scripting such as PHP need a LocalHost (The server on your computer) to run your scripts and test them freely.
Localhost can be access by entering the ip address http://127.0.0.1/ or http://localhost/ on your browser.
To do so you need to intall a barrage a installations such as apache server, PHP, Mysql etc on your computer which are complex and time consuming.
One really good options for Windows users are Wamp and Xampp
The advantage is by installing these you can install Apache, PHP and Mysql at one go and makes you scripting life easier.
After installation changing the setting, enabling or disabling any service (PHP, Mysql) is also a simple affair by a simple menu shown below.