As a developer, and tester at the same time, I need to have multiple operating systems to test my applications or even my design to get a better look of what the user will see. Of course I can not have multiple OS that dual boot on my system cause that would be painful especially when rebooting the main system to log into another one. Therefore I use a virtualization applications to operate multiple operating systems into one screen.

Here at my work we have a license to use VMware Workstation to test our applications, but when um at home, I can not afford the money to buy one, so I searched for open source and freeware that do virtualize different operating systems medium and here is a list of top 5 application you may want to use:

VMware Player

Get your copy at: www.vmware.com
A virtual machine is a computer defined in software. It’s like running a PC on your PC. This free desktop virtualization software application makes it easy to operate any virtual machine created by VMware Workstation, VMware Fusion, VMware Server or VMware ESX, as well as Microsoft Virtual Server virtual machines or Microsoft Virtual PC virtual machines. VMware Player is the easiest way to run multiple operating systems at the same time on your PC. With its user-friendly interface, VMware Player makes it effortless for anyone to try out Windows 7, Chrome OS or the latest Linux releases, or create isolated virtual machines to safely test new software and surf the Web. VMware Player can also be used to run a virtual copy of an old PC so that you can recycle the old machines you have under your desk or stored in the closet.

VMware Server

Get your copy at: www.vmware.com
VMware Server is a free virtualization product for Windows and Linux servers with enterprise-class support. It enables companies to partition a physical server into multiple virtual machines and to start experiencing the benefits of virtualization. VMware Server is a robust yet easy to use product for users new to server virtualization technology and is based on VMware’s proven technology. Begin enjoying the benefits of server virtualization for free. VMware Server is a hosted virtualization platform that installs like an application on any existing server hardware and partitions a physical server into multiple virtual machines.

Windows Virtual PC

Get your copy at: www.microsoft.com
Virtual PC provides IT Professionals with a cost-effective safety net for certain employees to run critical legacy applications on an interim basis while IT Pros continue their current migration plan to a new OS. Microsoft operating systems and applications running on VPC virtual machines are fully supported in compliance to the MS product lifecycle guidelines. So Windows XP Pro deployments can continue on schedule, even if faced with unanticipated application compatibility issues, allowing Microsoft customers to take advantage of the ROI and productivity gains of more current operating systems. With Microsoft Virtual PC 2007, you can create and run one or more virtual machines, each with its own operating system, on a single computer. This provides you with the flexibility to use different operating systems on one physical computer.

VirtualBox

Get your copy at: www.virtualbox.org
VirtualBox is a general-purpose full virtualizer for x86 hardware. Targeted at server, desktop and embedded use, it is now the only professional-quality virtualization solution that is also Open Source Software. VirtualBox has an extremely modular design with well-defined internal programming interfaces and a client/server design. This makes it easy to control it from several interfaces at once: for example, you can start a virtual machine in a typical virtual machine GUI and then control that machine from the command line, or possibly remotely. VirtualBox also comes with a full Software Development Kit: even though it is Open Source Software, you don’t have to hack the source to write a new interface for VirtualBox.

Sandboxie

Get your copy at: www.sandboxie.com
Sandboxie runs your programs in an isolated space which prevents them from making permanent changes to other programs and data in your computer. Running your Web browser under the protection of Sandboxie means that all malicious software downloaded by the browser is trapped in the sandbox and can be discarded trivially. Browsing history, cookies, and cached temporary files collected while Web browsing stay in the sandbox and don’t leak into Windows. Viruses and other malicious software that might be hiding in your email can’t break out of the sandbox and can’t infect your real system.