Install Latest Virtualbox on Ubuntu 13.4/13.10 from Official Repository

This simple tutorial is going to show you how to install Latest Virtualbox and receive updates on Ubuntu 13.10 Saucy, 13.04 Raring, 12.04 Precise.
To get started, press Ctrl+Alt+T to open terminal and follow below steps:
1.) Copy and paste this command into terminal and hit run to add the repository:

sudo sh -c 'echo "deb http://download.virtualbox.org/virtualbox/debian $(lsb_release -sc)  contrib" >> /etc/apt/sources.list'

2.) Download and install the key:

wget -q http://download.virtualbox.org/virtualbox/debian/oracle_vbox.asc -O- | sudo apt-key add -

3.) Update:

sudo apt-get update

4.) Install the Virtualbox:

sudo apt-get install virtualbox-4.2