Usage share of operating systems computer's installed base statistics, and actual (web) use needs not follow installed base. Also, Microsoft includes tablets (but StatCounter may also for Windows, while it wouldn't for e.g. Android). Video game store Steam publishes a monthly "Hardware & Software Survey", with the statistics below: By Q1 2018, mobile operating systems that can be found on smartphones, include Google's dominant Android (and variants) and Apple's iOS, with both combined at almost 100% market share. According to research by InsightPortal, there is a clear correlation between the GDP per capita of a country and that country's respective smartphone OS market share, Showing
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