How do computers work?
The average person who uses a personal computer on a frequent basis doesn’t think about what happens inside a personal computer once the electricity is switched on. As long as their version of MS Windows pops up within a few seconds, most people are quite happy to continue on with what they want to do on their personal computer. A personal computer goes through many processes from the moment the electricity is switched on before its operating system (ex. Windows, Linux) is fully loaded and takes over. The operating system is stored on the hard drive of a personal computer. It is stored on the hard drive because this kind of storage is much less costly and an operating system requires a large amount of storage space. So, in order to make personal computers more inexpensive, they are designed to use a mixture of ROM, DRAM, and hard disks. An account of each follows. Once the electricity switch is switched on, the “boot-up” process begins. To “boot-up” a personal computer merely means to
Computer hardware is like any other machinery. You can switch it on, and electrons will start flowing through it. That’s all that a computer can do. Like an ignorant being – computer needs to be told specifically what it should do. Computer programs are the tool to tell the computer what you want it to do. Computers understand only one language – the machine code. Machine code is a sequence of binary (1 and 0) digits. A microprocessor manufacturer (the microprocessor is the heart of a computer) decides which sequence of bits means what. Imagine that you want to construct your own microprocessor. You will incorporate various tasks in it. And you need to have a unique code for each task. A computer program will issue these codes to initiate the required task of the microprocessor. Let us consider the very basic task of moving a value into a register (a register may be thought of a microprocessor’s extremely fast internal memory).
A computer essential does one thing: it “computes.” In other words, computers work with number and do math. We are able to use computers to do a lot more than just math because programs have been written to hide the math behind the scenes. For example, when you are in a word processing program, every word you type is translated into numbers and stored in memory. For graphics applications like Photoshop, every pixel on screen is also recorded as a numeric value. Desktop computers (or “microcomputers”) became popular with the introduction of the Apple Macintosh in 1984, and since then they have helped to completely redefine the way we use computers. What was unique about the Macintosh was that it had a graphical user interface (GUI or “menu system”) and a mouse. Apple stole the GUI concept from IBM, and Microsoft in turn stole the concept from Apple. At the heart of the computer is the central processing unit (or CPU which does the math).
If you have ever wondered how computers work, here is a chance for you to understand the basics. While the technical aspects of what makes computers work could be difficult for a non-professional to understand, the mechanical aspects of it can give you a clear idea of what and how things happen inside a processor. Computers work thanks to a series of hardware devices that are closely interconnected. The basic components of a computer are the motherboard, or tower; the monitor; and the keyboard. The mouse may or may not be essential to the functioning of a computer, depending on the type and model. Most of the essential things that make computers work are inside the tower, away from your eyes. The central processing unit (CPU), located inside the computer tower, is the central stop for all the processes the computer goes through. As a command is sent, such as “open a program” or “turn the monitor on,” the CPU interprets this order and then acts accordingly. Once the computer is turned o
Dear Straight Dope: OK, after semi-exhaustive searching around your site, I have to ask this nagging question. How the heck do computers work? I know, this sounds like a simple question. But I find it hard to fathom millions upon millions of 1’s and 0’s floating around my processor every second that it’s turned on. How can a bunch of electrical currents run a highly complex game such as Quake2? I can’t comprehend it. Please, make me understand! — Josh Eikenberry It’s like this. Nobody knows. No one body that is. Except maybe Cecil. It’s all a matter of what we in the biz like to call “layers of abstraction.” Here’s how it works. Somebody builds a machine. A machine that can be programmed–that is, that can perform a series of simple steps, remember the results, make yes/no decisions based on some external stimulus, perform or not perform steps based on the results of the yes/no decisions, and skip either forward or backwards in the sequence of steps and keep going from that new spot. O
