The Main Parts Of A Computer

There we are sitting in front of our computer with lots of gadgets hanging around and connected to our computer. We may wonder what are the main parts to a computer.Well there are parts you can see and parts you cannot (inside that big box) There are parts that you cannot see just by looking. (Software).So what are the main parts of a computer? Lets look at the hardware first.The first thing is that us at home with our computer, don't call it that. We call it our PC that stands for Personal Computer. (We assume here that it is yours that why it's personal) They are called many other things but we don't really need to go into that.The term PC usually encompasses all the components of a computer (hardware and software)We are first going to discus the "Box", as this is essentially the computer. You know, the bit that you wish you could hide out of sight somewhere. Unfortunately the "box" contains all the stuff that is needed in a computer to make it one which the most important part is the:Central Processing Unit (CPU)The Central Processing Unit is usually a single large bit of electronics (A chip) that does all the work. It looks at the instructions from the software and acts accordingly. The CPU chip is typically a small thin square chip, which is seated firmly on a thing called a Motherboard (more on this later). The faster the CPU can perform these instructions the better. Unfortunately the more powerful the CPU the more your PC usually costs. If the CPU gets very busy it can get quite hot. To prevent this there usually is a fan and heat sink placed on it to keep it cool.The MotherboardThe motherboard so called because it contains lot of other parts that control your computer. (We have just seen that the CPU is one of these) Sometimes the term "Mainboard" is bandied around instead of "Motherboard") The "Motherboard" also contains the main paths to connections to your external devices. The "Motherboard" as well as the CPU being plugged into it can have other things plugged as well. e.g. a "graphics card"Computer MemoryComputer memory also plugs into the motherboard. Memory is needed to temporally store the software programs you are currently running on your PC. The CPU accesses the software instructions in the memory that you are currently running. Having this memory speeds up the process of running your PC programs and needless to say the more you have the better.If the PC did not have this memory then it would have to get the instructions from a Hard Disk drive which are extremely slow by comparison.A term most commonly used for memory is "RAM" (Random Access Memory) RAM usually comes in the form of a long thin PCB stick. Data stored in memory is not permanent and is lost when you switch off your PC. Another type of memory that is also on the motherboard is called Read Only Memory (ROM). This is a more permanent form of memory, and works similar to RAM. ROM can only be read from and not written to under normal circumstances. Data in ROM memory is not lost if the PC is switched off and is used to store important information that is required by the PC when switched back on again.Sound Card.The sound card sometimes called the Audio Card that acts as a dedicated CPU to process audio data. Most sound cards are in modern computers are now an integral part of the motherboard. Although these give reasonable sound quality you can also buy more expensive sound card that give higher quality sound. These can be plugged into the motherboard. In most cases the "Onboard" sound card is sufficient for most.Graphics CardThe Graphics Card, also called the Video Card or Adaptor is what controls what you see on your monitor. As with the sound card it can be part of your motherboard or a higher quality (and faster) one that plugs into the motherboard. Once again it has it's own CPU that is dedicated solely to processing complex graphics-related data. It usually also has its own memory. Displaying graphics takes an enormous amount of work and that is why most people (especially gamers) install a higher quality graphics card that can be quite expensive.Using a quality graphics card takes a lot of the work that the main CPU used to do making the display of images (specially moving ones) much faster, (this is why gamers install them)Power Supply UnitOf course with every electronic device power is needed. This is provided by the Power Supply Unit that is also internal to the box. The power supply converts the mains power to the voltage levels that are needed to drive the various electronic components. Wires with plugs on the end are used to distribute the power to the various components. There are usually spares that are used if extra components are installed in the PC.Disk Storage Drives.As main memory (RAM) is only a temporary storage facility we need somewhere to store all our stuff permanently. I'm sure when you bought your PC the salesperson (being politically correct here) spouted on how many gigabytes hard disk storage the PC has.Hard disk drives are plugged into the motherboard via cables from the back of the disk drive. The motherboard in most cases has a built in disk drive controller although on much higher powered PC's there are plug in controller boards.Hard disk drive data is semi permanent, that is things can be written to them and deleted from them. They are also sort of semi random access but can only randomly access complete files not data within a file like you can do with RAM.On big problem with hard disk drives is that they can become fragmented. This when, specially on large files the bits of the files get placed on different parts of the disk. This occurs because of deleting and writing files down to the hard disk. This occurs over time and can be fixed by periodically "defragmenting" the disk with "Windows" utility"A term that is going rapidly out of fashion is another type of disk drive called a "Floppy Disk Drive" PC's nowadays don't even have one of these installed as they have rapidly been superseded by memory Sticks and Cdrom drives The last type of disk drive is and Optical Disc Drive  more commonly know as a CDROM drive or a DVD drive. These use a laser to read or write to a cdrom or dvd disk.Display or Monitor DeviceA PC would be useless without one of these as it is what shows the results of all the work the CPU has done. Data is display on the screen of the monitor. These days they tend to be LCD monitors the old CRT heavy monitors rapidly going out of style. I even doubt if you can buy the old style new any more.In the main the output is displayed graphically. This graphical data usually comes directly from the graphics card. Nowadays modern PC's can also be plugged into a television set of any type, such as CRT, LCD, Plasma, Rear or Front Projector. Monitors have the ability to display graphics at different resolutions. These are usually expressed in so many pixels wide by a number of pixels high (e.g. 800x 600 or 1024 x 768 and higher). A pixel is a single dot on the screen. The higher the resolution the clearer the image. Cooling DevicesLike all electronic devices (yes that’s all a PC is) they can generate a lot of heat, especially when they are being used heavily. We have already spoken about cooling for the CPU but the rest6 of the components need cooling as well. A fan is incorporated into the "Box" to  cool the inside of the case.The PC Case.This is what hold all the electronic components, The motherboard, CPU, controllers, Diskdrives and more plus of course the Power Unit. The Case is usually ventilated at the back and at least one side (usually where the CPU heats sink fan is ventilated) A common mistake with PC owners is to place the case hard up against something restricting this flow of air from the case side. This can sometimes be seen by strange things happening when you are using the PC (system suddenly reboots, get funny errors) This is caused by overheating. Modern PC's usually have a overheating cut out that drops the power as well. PeripheralsThis is a term used to describe anything attached externally to the PC. Printers, external disk drives and such. Even your keyboard and mouse are classed as a peripheral. Operating System and SoftwareWe have now reached the parts of a computer you cannot see you only see the results of what they do on your screen.The first of these is the Operating System, such as Windows XP. This is the most necessary piece of software as it tells all the hardware and software components in a PC what to do to achieve a desired result. In other words, It is the boss and controls everything. The term software, is a more general term, referring to a collection of instructions which perform a particular task, more generally called programs. Itunes we probably all know is software that allows you to download music or videos and play them. Outlook Express is a program that manages all your e-mail. Whatever they are they still run under the control of the "Operating System".So there you are a brief understanding what all the main parts of a computer are. Don't forget  if you wish to go into the workings deeper have a look at "How Computers Work"