Theos Software Inc has added support for MS-DOS applications under its proprietary multi-user Theos operating system for iAPX 86 family machines. The Theos system runs on a standard 80286 or 80386-based PC with terminals attached, the 80286 version handling up to 60 terminals and the 80386 version more than 100. The operating system appeals to users who would once have had to use a multi-user minicomputer, and is attractive because it is cheaper than multiple personal computers on a local area network, according to the Walnut Creek, California company. The new Theos-DOS feature, reports Microbytes Daily, creates a virtual personal computer within Theos when MS-DOS is booted, so it can run character-based MS-DOS software from an 80-by-25-character terminal. And with a Sun River graphics terminal, Theos-DOS runs graphics-intensive software such as Microsoft Windows, complete with mouse. No prices. Theos is marketed here by Midshires Computer Services Ltd, Crewe.