Android (operating system) wrote in "The New York Times" that "About one of every two computers sold today is running Android. [It] has become Earth's dominant computing platform." According to a Statistica's estimate, Android smartphones had an installed base of 1.8 billion units in 2015, which was 76% of the estimated total number of smartphones worldwide. Android has the largest installed base of any mobile operating system and, since 2013, the highest-selling operating system overall with sales in 2012, 2013 and 2014 close to the installed base of all PCs. In the second quarter of 2014, Android's share of the global smartphone shipment
Operating system followed by Apple's iOS with 12.1 percent and a per year decrease in market share of 5.2 percent, while other operating systems amount to just 0.3 percent. Linux distributions are dominant in the server and supercomputing sectors. Other specialized classes of operating systems, such as embedded and real-time systems, exist for many applications. A single-tasking system can only run one program at a time, while a multi-tasking operating system allows more than one program to be running in concurrency. This is achieved by time-sharing, where the available processor time is divided between multiple processes. These processes are each interrupted repeatedly