Operating System (OS)

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You and your computer speak different languages.  Computers don’t speak English, nor Spanish; they only speaks in 0s and 1s.  Man and computer cannot communicate directly, which is why an operating system is needed.  The operating system (OS) is a program that allows you to interact with the computer.  Together, the operating system and the computer hardware form a complete system that determines what your computer can and can’t do.

There are many different operating systems.  Two of the most common ones are Microsoft Windows and Mac OS X.  Windows comes preloaded on most personal computers, whereas Mac OS X run only on Macs.  However, operating systems are not just for computers and laptops.  Mobile devices run on mobile operating systems like Apple IOS or Google Android—operating systems for portable devices are designed for interactions with smaller touch screens.  Before downloading new software or applications to your computer or mobile device, you should always check to see if the application is compatible with your operating system.  Some applications work on all operating systems, but others only work on certain ones.

When every operating system turns on, a self-sustaining snowball style process known as a bootstrap must cycle through an automated chain of functions that gradually increases access to system hardware and controls.  Once this is done, the OS becomes completely responsible for detecting what it and all the other programs need from the hardware, as well as being responsible for meeting those needs as quickly as possible.

Device drivers are loaded as part of the booting process. These pieces of equipment enable hardware makers to write the code once, and allow it to work on a wide variety of systems running the same (or even merely similar) operating systems.

As soon as you interact with your computer, the software you’re using will send out something called a system call, which specifies a task that a hardware component must perform in order for that software to continue functioning and to send further requests.  Once the operating system has registered these requests, it undergoes a very important phase, which is gathering these requests for for organisation and processing.  Bearing that in mind, when a program is first initiated it needs some system memory in order to get up and running.  It sends out a call which is received by the OS’s memory manager.  Once that call has been translated into the hardware’s language, the OS will slot them into active keys based on the amount of memory it feels is necessary: this quality is also known as its block size.  When the program is later closed, the OS will terminate the blocks which it had previously allocated for that program, and either reserve them for other programs or just leave them empty, as needed.  In this fashion the OS is constantly receiving calls and altering queues, making use of system managers for everything from processes, to files, to networks, and to devices.

Understanding this, the question now becomes: how does the OS and its system managers determine which programs are the most important?  The answer is based on what we click. The second—and often the most confounding—function of the operating system is to provide us with a graphical user interface that includes everything from the sign-in buttons, to the task bar design, and even that annoying little beach ball that never stops spinning. If it’s done correctly, the UI basically gets out of the way so we can tell the computer what to put at the top of the queue.  For example, by maximizing it on the whole screen, the game we’re trying to play pops up, not the anti-virus.  That’s an example of the kind of multitasking behavior that the operating system can carry out.  Without multitasking, modern OS’s wouldn’t be able to share resources between different tasks, especially ones running in the background, behind what you’re actually focused on.