Usage share of operating systems Usage share of operating systems The usage share of operating systems is the percentage of computing devices that run each operating system at any particular time. All such figures are necessarily estimates because data about operating system share is difficult to obtain; there are few reliable primary sources—and no agreed methodologies for its collection. In the personal computing platform area of smartphones and watches two systems dominate: Google's Android with over 2.7 billion users and Apple's iOS and macOS combined with over 1.3 billion users. In the area of desktop and laptop computers, Microsoft Windows is generally above 75% in
RCA Spectra 70 the Spectra 70 CPU were announced around 1965, ranging from a small system (70/15) to the large scale (70/55). Some of the main features were: These systems all ran RCA's real-memory operating systems, DOS and TDOS. The systems that supported virtual memory, the Spectra 70/46 and 70/61 and the later RCA 3 and 7, could also run the RCA's Virtual Memory Operating System (VMOS). VMOS was originally named TSOS (Time Sharing Operating System), but was renamed to expand the market for the system beyond time-sharing. TSOS was the first mainframe, demand paging, virtual memory operating system on the market. The