1. Operating System definition
1.1. Definition: software that controls and manages hardware and basic system operations for a computer. The operating system loads programs into the computer's memory, runs these programs, and manages peripherals like disks and printers.
1.2. www.iolo.com/labs/Glossary.aspx
2. Chromium
2.1. Chromium OS is an open-source project that aims to build an operating system that provides a fast, simple, and more secure computing experience for people who spend most of their time on the web.
2.2. http://dev.chromium.org/chromium-os
3. Windows 7
3.1. Pros
3.1.1. Most popular operating system
3.1.2. Applications & driver support – Undoubtedly Windows has the most number of applications
3.2. Cons
3.2.1. Not free, restricted, no freedom
3.2.2. Because of the high usage, most spywares and viruses are targeted to this platform.
3.3. http://blog.hafees.com/windows/windows-linux-and-mac-a-comparison/
4. Mac OS X
4.1. Pros
4.1.1. Targeted less by viruses & spywares
4.1.2. Applications – A large number of excellent professional applications are available in this platform and hence preferred by designers and other professionals.
4.2. Cons
4.2.1. Cost of ownership is high – User is not free to try it out by paying for the operating system alone, instead the user is forced to buy new hardware at premium prices.
4.2.2. Though, based on open source operating systems, it is still proprietary
4.3. http://blog.hafees.com/windows/windows-linux-and-mac-a-comparison/
5. Ubuntu
5.1. Pros
5.1.1. Free software – No cost, no restrictions – complete freedom.
5.1.2. Excellent community – Most of the Linux distributions (or simply called as a distro), especially Ubuntu has excellent community support. So if you ran into a problem, just seek help from the community.
5.2. Cons
5.2.1. Unstable – While it is true that Linux is one of the most stable and secure operating systems, you might’ve experienced many crashes.
5.2.2. Installation may be difficult if your hardware is not standard (less available or less popular).