With an introduction of smartphones, Google's Android and Apple's iOS have entered the operating system(OS) market that had been led by Microsoft. Competition to grab the leading market position is fierce as dominating the OS market would mean controlling related industries including electronic gadgets, TVs, automobiles and cameras that can be connected to apps. In addition, if the cloud system advances further, it will open a new, reorganized OS market. Samsung Electronics is said to be recently working with Intel to develop Tizen, a new mobile operating system. So, why are the global IT giants focusing on the OS? Let's find out the OS market's potential and significance through the ongoing competition in the market that is increasingly getting fiercer.