From Wikipedia, the free encyclopedia
Jump to: navigation, search
History of IBM mainframe operating systems

BESYS (Bell Operating System) was an early computing environment originally implemented as a batch processing operating system in 1957 at Bell Labs for the IBM 704 computer. The initial version of the system BESYS2 was created by George Mealy and Gwen Hansen with Wanda Lee Mammel under the guidance of Victor A. Vyssotsky and utilized IBM's FORTRAN and North American's symbolic assembly program (SAP) programming languages. It was designed to efficiently deal with a large number of jobs originating on punched cards and producing results suitable for printing on paper and punched cards. The system also provided processing capabilities for data stored on magnetic tapes and magnetic disk storage units. Typically punched card and print processing was handled off line by peripheral IBM Electronic Accounting Machines, IBM 1401 computers and eventually direct coupled computers.

Internal use[edit]

BESYS was used extensively by many departments of Bell Labs for over a decade. It was made available through the SHARE organization to others without charge or formal technical support.

BESYS versions[edit]

Versions of the BESYS environment (BESYS3, BESYS4, BESYS5, BESYS7 and BE90) were implemented as the underlying computers transitioned through the IBM 709X family and IBM System/360 Models 65 and 67 computers. Throughout this period the head of the BESYS development project was George L. Baldwin. In the 1960s, when Bell Labs sought to transition to a more advanced time sharing environment, principles and experience from this project loosely influenced the development of Multics.