VirtualBox is a cross-platform virtualization application that allows multiple operating systems at the same time. You have to use any different operating system in One computer. But before you install operating system on VirtualBox you should know how to set some settings for secondary operating system.
In this helphin will guide How to set Virtualbox for Ubuntu Operating system. These are the basic settings really you should know.
Some developers are test their application or softwares on localhost using XAMPP server. but most of application needs database application username and password. for example some CMS needs database username and password. but XAMPP or WAMP server Phpmyadmin application has login with null password. so we are not able to install that CMS application on localhost. So first we need to set phpmyadmin password. This Guide show you How to set Phpmyadmin password on WAMP / XAMPP Server.