Operating Systems

Your computer is basically just a bunch of metal, wire, and circuits. It can't do anything without a program and a person to interact with. There are many programs in the world designed to do specific things, for instance working with graphics, or word processing. These programs allow the person to do the tasks they need, but they do not fully communicate with the entire computer system. You can imagine it as two people from different countries that speak different languages and have different agendas. The operating system of the computer is like an interpreter that pulls everything together and speaks with all the different programs and hardware allowing everything to work properly.

The computers we know today are descendants of room size monsters who ate data from punch cards and took hours to do one math problem. Most computer users would not recognize ENIAC as a computer. ENIAC (Electronic Numerical Integrator and Computer) was born in 1946 and weighed 30 tons. (Kempf, 1961) ENIAC did not have an operating system instead every action it did was dictated on the data inserted via its punch cards. (Kempf, 1961) This was a tedious process that greatly limited what ENIAC could and could not do.

A better system would not come into existence until the early 80's when DOS (Disk Operating System) was born. DOS allowed the user to pick from a list of functions or commands using a keyboard. These were loaded onto the computers RAM (Temporary Random Access Memory) by a floppy disk or boot disk that contained all the computers system files in a process called booting up. (Knetzger & Muraski, 2008) DOS would be our first operating system and would usher in a massive growth in the computer industry and be the forbearer of many operating systems to come.

Booting a computer today is a much different process. I will break it down very simply. When you turn your computer on the first thing that happens is the system runs some basic tests on its hardware. After this is completed and deemed ok the computer moves on to testing its processor, RAM, and BIOS. Once this step is finished the computer accesses the BIOS which hold very basic instructions that allow access to storage devices and a few other things. Once the hard drives are up and running the computer can access the MBR. The MBR (Master Boot Record) contains information that allows the system to access the OS (Operating System). Once the OS is loaded it begins to load device drivers such as the mouse, keyboard, graphics, sound, etc. When this is finished the computer is ready for use. (Knetzger & Muraski, 2008) This entire process is displayed on the screen and a user can easily follow the computers progression.

When it comes to file types and extensions you have to remember that every operating system will have extensions unique to them. That means Windows will differ from Mac. Some of the most common file extensions you will encounter are: .txt, .dat, .dll, .bin, .asp, .avi, .bat, .bmp, .mp3, .cab, .chk, .doc, .ext, etc. (Knetzger & Muraski, 2008) The list goes on and on but you get the point.

References

Knetzger, M & Muraski, J. (2008) Investigating High-Tech Crime. New Jersey, US: Prentice Hall

Kempf, K (1961) Electronic Computers within The Ordnance Corps. U.S. Army