What's in the box?

I'm sometimes caused confusion when clients describe their problems and this is down to terminology used. I get told that "the modem doesn't work", or that "the hard drive won't start" when, on further questioning, it turns out that these aren't the components that are causing the problems, just the names that some folk use to refer to their computer so I thought I'd just give a simple guide to the bits that are in a typical computer.

Firstly, note that I'm not referring to laptops (at this stage) but to the common lump of machinery that lives in some sort of case and has attachments such as keyboard, mouse and screen.

OK, let's start with the box itself. This is the case which houses all the workings and may be referred to as the "base unit", the "computer" or just the box! It also comes in different shapes and sizes but we'll not worry about that here.

Inside the box are a small number of components;

Power supply - this is the lump of electronics that takes your mains electricity and converts it into the voltages needed by the computer. It is not uncommon for these to 'die', particularly if there has been lightening around so if your computer does absolutely nothing - no whirring sounds, no flashing lights - then probably you've got a dead power supply.

Motherboard - this is the main circuit board which contains all the components that make up the computer. In fact it's sometimes called a main board. On the motherboard are a few particularly important components (well, they're all important really, else they wouldn't be there!) such as the processor (sometimes known as the CPU = Central Processing Unit) and the memory. The processor is the brain of the computer and the memory is the storage which is used by the computer when it's switched on. Note that this is not the same as the data you store on the disk drive (see later); when the computer is switched off, everything in the memory is lost.

disk drive (sometimes called the hard drive) - this is the permanent (well nearly permanent!) "memory" of the machine but it can cause me confusion if you refer to it as memory! Think of it as the computer's filing cabinet. It's where all your data is stored as well as all the programs you install. Do remember, however, that it's only a permanent store for as long as it's working! If a drive crashes then you can lose ALL of your data so make sure you have a backup of all your important stuff. Programs can be reloaded but what about those precious photographs?

CD drive (or DVD drive) - first there were CD readers, then CD writers, then DVD readers and now DVD writers are common. A modern machine will normally have a DVD writer and this will be able to read or write both CDs and DVDs. These can contain files just like on a hard disk drive or they can contain audio or video tracks which can be played in normal CD and DVD players.

Floppy Drive - once common, these drives are becoming less so. They are very unreliable and it's always best to assume that anything you write to a floppy disk (the 3.5" square thing that goes in the floppy drive) will probably be unreadable. If it's important, make at least two copies. The capacity of a floppy disk is only around 1.4MB which is about enough to hold just one photograph. Increasingly, modern machines are produced without such drives and if you want one you may have to pay extra to get it.

additionally there may be a number of "expansion cards" which provide extra facilities...

Graphics Card - this is a circuit board which plugs into the motherboard to drive your monitor. They vary greatly in capability and price and the more powerful ones have computers of their own on board (known as Graphics Processing Units). Such cards are used for high-performance graphics applications, such as modern games and prices can exceed £1000! For normal email, word processing and the like, a simple card is all that is required (probably costing around £30) and very often the motherboard will have a perfectly adequate graphicsfacility built in to it.

Sound card - In order to hear sounds on your computer (other than a few beeps from its internal speaker) it needs a sound card (although, again, this functionality is very often built in to the motherboard).

Modem - this stands for modulator-demodulator and in this context is a device which converts signals between computer-speak (binary) and some other form. In the case of a normal modem, this means into sounds which can be sent down the phone line. In the case of a broadband modem, it converts between binary and a higher frequency signal.