USU (operating system) USU (operating system) USU linux (Bulgarian: УСУ; Учи Свободен с Убунту) is Bulgarian open source desktop operating system built around the KDE desktop environment and based on the popular free Linux distribution, Ubuntu. Usu can be downloaded in three flavours, Desktop, Mini and Netbook, each one with its own features and target audience. All of them can be downloaded for free, as Live CD/DVD ISO images, supporting 32-bit and 64-bit processors. The defult language is Bulgarian, but in installation it can be easy changed with F2 key. USU Desktop is created to be used as a learning tool, this edition
Time Sharing Operating System Time Sharing Operating System Time Sharing Operating System, or TSOS, is a discontinued operating system for RCA mainframe computers of the Spectra 70 series. TSOS was originally designed in 1968 for the Spectra 70/46, a modified version of the 70/45. TSOS quickly evolved into the Virtual Memory Operating System (VMOS) by 1970. VMOS continued to be supported on the later RCA 3 and RCA 7 computer systems. RCA was in the computer business until 1971 when it sold its computer business to Sperry Corporation. Sperry renamed TSOS to VS/9 and continued to market it into the early 1980s. In the