OPS101 ASSIGNMENT: Write an essay to describe the evolution of operating systems from the early 1940s until today

Evolution of Operating Systems

      Operating Systems have come a long way since the 1940s.  The first generation of computers was literally the size of a classroom, requiring little need for an operating system.  In 1955, the second-generation computers were introduced.  Computers at this time were still very expensive, averaging $200,000. The third-generation computers didn't come along until the mid-1960s. These were designed with faster CPUs. In 1976 the first supercomputer was produced. By the 1980s, computers started using multiple processors, which now required a new type of operating system. In 1990 the Internet became extremely popular, and the 2000s brought the ability of virtualization, the ability to run multiple operating systems on top of a single operating system.

      First-generation computers were literally run by programmers. The way the system was debugged was by literally stopping the machine, adjusting the register, and then restarting the system. Programs could only be edited by its creator due to the fact that the programming language was so unique. Needless to say, at this time the CPU was utilized poorly. By the second-generation, computers could now job schedule which slightly improved efficiency. There was still an imbalance between the CPU and I/O devices, causing extensive time lag. It was common for the CPU to be idle 94% of the time. Eventually I/O devices became faster, and blocking was used, allowing several logical records to group within one physical group. The third-generation brought multiprogramming, which allowed multiple programs to be loaded at once to share the attention of the CPU. Eventually using multiprogramming, operating systems were able to take multiple slices of programs, and feed them into the CPU when needed, greatly increasing efficiency. By the late 1970s virtual memory was now possible, making it so that programs didn't have to reside in the memory to run.

      The operating system pretty much had to step up its role in the computer system as soon as virtual memory became possible. Because of the increase of efficiency, to get the most out of the computer, operating systems now, not only had to control the subsystem manager and devices, but had to do it both user-friendly and efficiently. By the 90s, the Internet boom brought networking. Operating systems now had the ability to use remote desktop capabilities, or control other computers without physically being at the computer. Today, in 2012, we have the ability to use virtualization, which allows us to run multiple operating systems, such as Linux, on top of our main operating system, allowing a number of possibilities. Just the thought of that alone, is enough evidence to show how drastically operating systems have been improved in just 50 to 60 years.