A computer consists of a whole bunch of pieces and only a very few of them are visible. The obvious ones are those designed to allow you to interact with the machine, things like the keyboard, the mouse, the display screen and maybe some speakers. There's other odds and ends that can be attached to the computer like modems, printers, network cables, scanners and cameras and whatever else plugs in. These things are called, peripherals, devices that are added to a computer without actually being the computer. A computer can be configured to live quite happily without any of these devices but it won't be much fun to use. The peripherals are the only way you can "communicate" with a computer; they are the human interface. The actual computer, the thing that makes all the other pieces meaningful, is hidden away inside a metal box. To get to the computer, you have to open the box and peek inside. Scary stuff if you've never done it before. The only tool you'll need is a Phillips screwdriver so that part is easy enough. Every computer manufacturer has its own way of designing the case so you may have to poke around to find out the magic combination that opens the thing. Typically you will just unscrew some screws and wrestle the case open.

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Once you've opened the case you can see the stuff inside and, usually, access all the components. There's going to be various cables blocking your view. Some cables will be to distribute power. These will have white plastic connectors with colored wires inserted into them. The colors are usually yellow and red on the outside edges and black on the inside two wires. There will also be a large white plastic connector that attaches to the Motherboard. This connector will have more wires than the others and it's about twice as big so it's easy to locate. These cables are for power.

Other cables will be wide, flat cables usually gray in color. These are used to connect to disk drives: CD, hard disk, floppy disk, ZIP disk, DVD, etc. These cables will be marked on one edge with either a color or pattern to distinguish one edge from the other. The cable edge having this mark is supposed to connect to pin one of the device ( a "pin" is the term used to describe one of the wires the cable plugs into).

If you remove all these cables you'll be able to see the Motherboard. This is the big circuit board into which other circuit boards are inserted. Some of these plugin circuit boards (also called "cards" or "adapters") are for things like video, modem, sound, scsi, IDE and I/O extensions, networking (ethernet, DSL, etc.) and other specialized circuits. These cards are actually extensions to the motherboard. The main computer is still the motherboard, but additional capabilities are added by plugging in these cards.

There are other things inserted into the motherboard also. The main system memory is added as plugin modules. Sometimes the BIOS might be replaceable so it will also plug in. There is a battery that can replaced as well. You can add and replace fans if you want and even the CPU (the heart of the whole computer).

What this means is that the motherboard is just the most basic component of the computer. The really useful features and capabilities have to be added. Once everything is added and properly connected, the motherboard has been expanded way beyond its original capability. Knowing that, you can appreciate the need to understand how all these pieces work together.

You can add a card by inserting it into a connector. The connector has to be the same as the one on the card you are adding. Most PCs now only support the newer type connectors called PCI. Sometimes you'll also see a much larger connector that's included so you can use older cards. This type of connector will be an ISA connector (a connector is also called a "slot"). There's another type of slot used solely for graphics called AGP. Fortunately each of these slot types are unique so you can't accidentally put the a card in the wrong type slot - it won't fit. While it's possible to mis-configure your computer by using cards that don't quite match the motherboard specifications, the result will usually be harmless. At worst the computer will under-perform but damage is unlikely.

Every part in the computer is really pretty rugged and can survive bumps and even being dropped. What these components don't like however is "bad" electricity. This is electricity that varies from a narrow range of values. A computer power supply will provide some protection but you shouldn't count on it. Make sure you have an Uninterrupted Power Supply (UPS) and plug the computer into it. A UPS uses a battery to provide power if the main electrical supply fails. Much more importantly, the UPS has circuitry to filter and condition the incoming power so that the computer power supply always receives clean and stable electricity. You gotta have one of these. NOTE: Do NOT plug a printer in to a UPS - it will damage the UPS.

Another threat to your computer's health is heat. Electronic devices don't like heat. Make sure you put the computer where there is some ventilation. Since the computer will tend to create electrical fields, it will also attract dust. If enough dust accumulates on an electronic device, it will over-heat. If a device gets too hot it will begin to fail. At first it might be intermittent but if it goes on too long, it might fail completely. If the environment in which you use the computer is hot, add some fans to the computers case and keep it off the floor so air can circulate all around it. Put a cloth cover over the computer whenever it's turned off to slow down the accumulation of dust.

If you decide to open up your computer and poke around inside, keep in mind that all electronic circuits respond to static electricity. Enough of a discharge can damage a circuit. Since the computer case is metal you can just touch it before handling anything else. Touching the case gives you the same charge as all the stuff inside so there is no danger of frying a circuit when you handle it.

What all this means is that you can, and you should, open up your computer and check it out. Get to know what's going on and where things are located. Write down the manufacturer and model number of every device. If you have problems later on you can either call Tech Support or search the Web to get information on the failure. Once you know what you're dealing with, you increase your chances of fixing it yourself without paying a bundle to someone else for what may be a very simple solution.

There's a few terms that are often mis-used that not only confuse those using them but anyone trying to understand what they're trying to explain. If you have to explain a failure of some kind, use the correct terminology to make sure the right things are getting attention. Some of these terms are:

• Memory: This one is often confused with disk storage. Memory is used to store data that the CPU is going to process. It is composed of Integrated Circuits (chips or ICs) that plug into the motherboard. The amount of memory determines how fast a process takes to complete and how many processes can coexist without crashing the machine. More is better. In most computers a minimum of 128Mb will usually be fine but, again, more is better. Each memory chip will have a speed rating and a capacity rating. In some cases it will also do some error checking to validate data (ECC). There's lots of different kinds of memory both in capabilities and physical design so you have to make sure that the memory you add to your computer is the right kind.

  There is also video memory but that will be installed on the video card. This is used to render complex graphics very fast and with very high resolution. You should have a minimum 32Mb. The are some computers that use "Shared Memory" for video. This is not a very good design since it will "borrow" memory from the main system memory pool (the memory the CPU uses). This can limit the speed and usefulness of the whole computer.

• Mass Storage: This refers to devices like disk drives and includes floppy drives, hard drives, ZIP and LS120, CD, DVD and tape. These are NOT the same as memory. Data on these devices is loaded into the main system memory to be processed by the CPU. The CPU may copy (write) processed data back to one of these devices from main memory. Most of these type devices have all the circuitry necessary to handle their own tasks without interfering with the operation of the other processes.

• CPU: This is an Integrated Circuit (IC) that takes data from the system memory, processes it and then does something based on what the process required. It may also put data back into main memory to make it available to some other device such as a disk. The CPU is NOT the computer case. Referring to the case as the CPU will confuse whomever you are talking to.

• The Internet: This is a common one. If you try to reach a website and it "times out" or cannot be reached, it may just be that one site. Try several to see if any of them work. If one website will work but others won't it's because that site has failed - not the Internet. There are ways to check: ping will check to see if your computer can make a connection to another computer. tracert will try to connect to the other site and show you how it makes the connection. To see how to use these commands try a web search for help.