This operating system was based on the original Chippewa Operating System. In the early 1970s, it was renamed NOS/BE for the CDC Cyber machines. The SCOPE operating system is a file-oriented system using mass storage, random access devices. It was designed to make use of all capabilities of CDC 6000 computer systems and exploits fully the multiple-operating modes of all segments of the computer. Main tasks of SCOPE are controlling job execution, storage assignment, performing segment and overlay loading. Its features include comprehensive input/output functions and library maintenance routines. The dayfile chronologically records all jobs run and any problems encountered. To aid debugging, dumps and memory maps are available. Under control of SCOPE, a variety of assemblers (COMPASS), compilers (ALGOL, FORTRAN, COBOL), and utility programs (SORT/MERGE, PERT/TIME, EXPORT/IMPORT, RESPOND, SIMSCRIPT, APT, OPTIMA etc.) may be operated. The computer emulation community has made repeated attempts to recover and preserve this software without success.