Oracle VirtualBox was mainly built by Innotek GmbH under the supervision of Sun Microsystems; however Oracle Corporation bought it after some time. It supports the creation of virtual host machines and manages the guest servers in a great manner. It was first released in the year 2007 and since then it has been improvised to an advanced level. Its latest stable version has been released recently in December 2015 to help both professional as well as private users. It is open source software that can be downloaded and used for free.