This paper presents a comparative study of choosing footstep of Windows, Linux and Mac, the three popular operating systems. This paper provides seven factors which needed to be considered before choosing an operating system. They are convenience, capability, security, interface, recovery, booting time and cost. These seven factors were generated from background study and analysis. Some important characteristics such as dependency upon hardware, user interface, and security are also discussed. Moreover, opensource and closed source paradigm were discussed for user support. Finally, based on user data, it has been shown how these threeoperating systems are used by users in the last couple of years.