Setting up Apache, MySQL, PHP and Perl is not an easy task for those who have never done it before. This is a common, cheap (free) and efficient development environments for many reasons.
LAMP is term for such a cheap and powerful development environment. Linux, Apache, MySQL and PHP. It is also possible to set these up on a Windows environment quite easily too.
XAMPP is a distribution made for Linux, Windows, MacOs and Solaris by the Apache Friends. The install provides you with a preconfigured Apache, MySQL, PHP and Perl environment after an easy install process. The package is free to download and use.
A package like XAMPP is great for people who want to develop and test their websites on their local machine before deploying such to their production environment. Testing is always a good idea, particularly for a website with a lot of visitors.
There are other similar packages available such as: