1. OPERATING SYSTEM DOS BACKWARDS

2. 1970’s…
Dos-11

3. DOS-11
BATCH-11/DOS-11, also known simply as DOS-11, was an operating system by Digital Equipment Corporation (DEC) of Maynard, Massachusetts. The first version of DOS-11 (V08-02) was released in 1970 and was the first operating system to run on the Digital PDP-11 minicomputer.

4. 1960’s…
Unics
Tss-8
Waits
Dos/360
Os/360
Exec 8
Gcos
IBSYS

5. unics
Unix (officially trademarked as UNIX, sometimes also written as Unix with small caps) is a computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna. Today the term Unix is used to describe any operating system that conforms to Unix standards, meaning the core operating system operates the same as the original Unix operating system. Today's Unix systems are split into various branches, developed over time by AT&T as well as various commercial vendors and non-profit organizations.

6. TSS-8
TSS-8 was a little time-sharing operating system co-written by Don Witcraft and John Everett at Digital Equipment Corporation in The operating system ran on the 12-bit PDP-8 computer and was released in 1968.

7. WAITS
WAITS was a heavily-modified variant of Digital Equipment Corporation's Monitor operating system (later renamed to, and better known as TOPS-10) for the PDP-6 and PDP-10 mainframe computers, used at the Stanford Artificial Intelligence Laboratory (SAIL) up until 1990; the mainframe computer it ran on also went by the name of "SAIL".

8. Dos/360
Disk Operating System/360, also DOS/360, or simply DOS, was an operating system for IBM mainframes. It was announced by IBM on the last day of 1964, and it was first delivered in June 1966.[1]
DOS/VS was further development, released in 1972, as the virtual memory mechanism became available on new System/370 series hardware

9. OS/360
article or section. (Discuss)OS/360, officially known as IBM System/360 Operating System,[1] was a group of batch processing operating systems developed by IBM for their then-new System/360 mainframe computer, announced in They were among the earliest operating systems to make direct access storage devices a prerequisite for their operation.

10. EXEC 8
EXEC 8 (sometimes referred to as EXEC VIII) was UNIVAC's operating system developed for the UNIVAC 1108 in It combined the best features of the earlier operating systems: EXEC I and EXEC II (used on the UNIVAC 1107). EXEC 8 was one of the first commercially successful symmetric multiprocessing operating systems. It supported simultaneous mixed workloads comprising batch, time-sharing and real-time. It supported one file system with a flat naming structure across many drums and/or spindles. It supported a well-received transaction processing system. Unisys continues to market and support systems founded on the original 1108 and EXEC 8 designs.

11. GCOS System architecture and concepts
GCOS is a multithreading, multiprogramming operating system originally oriented towards batch processing, although later versions incorporated enhancements for timesharing and online transaction processing environments. Systems running GCOS today use it mainly for batch and OLTP, or as a backend enterprise server.

12. IBYSYS
IBSYS was the tape based operating system that IBM supplied with its IBM 7090 and IBM 7094 computers. A similar operating system (but with several significant differences), also called IBSYS, was provided with IBM 7040 and IBM 7044 computers. IBSYS was based on SHARE Operating System.