Basic Concepts and Vocabulary

Here are the basic components of any computer system; you need all of these. (Embedded links are to later in the page--click on them to skip ahead, or just read straight through.)

Here are additional components that you probably want:

In order to understand what you are buying, you need to understand a little about what's inside your computer. In particular, you need to know about the CPU, RAM, and hard disks.

The CPU
The CPU, or Central Processing Unit, is a component somewhere within the computer, and is the "brain" of the computer. There are many kinds of CPUs, and they mostly have numbers rather than names. Here's a quick rundown:

PCs use a CPU made by Intel. These CPUs are called the 80186, 80286, 80386, 80486, and Pentium. Since the 80 is always there, people refer to them by the last three digits, e.g. "four-eighty-six". Smaller numbers are older, slower, and generally no longer on the market. The Pentium, the only one with a name, is the newest and fastest.

Macintoshes use a CPU made by Motorola. Older ones are called the 68000, 68020, 68030, 68040--as a group, these are called the 68K Macs. Again, larger numbers are newer and faster. Newer Macs are called Power Macs and use a PowerPC 601, PowerPC 603, PowerPC 603e (or 603+), or PowerPC 604. Don't get confused by the "PC" in the name: these are Macintosh CPUs. The 604 is newest and fastest, while the others are approximately equivalent.

Software written for Motorola CPUs will not work on Intel CPUs. Software written for Intel CPUs will not work on Motorola CPUs. In other words: Software written for Macintoshes will not work on PCs. Software written for PCs will not work on Macintoshes.

So what about those TV advertisements that claim you can run PC software on a Mac? Well, let's call them "misleading." You can do it, but it's not automatic, and it's not cheap. You can buy a special software package, called SoftWindows, that will allow a Macintosh to run most PC programs--it costs about $300, depending on the version, and is slower than it would be on an equivalent actual PC. Or you can buy a hardware card for about $500 to $900 that fits into some (but not all) Macs and runs at full speed. A few (very few) Macs come with this hardware card pre-installed.

As far as I know, there is no way at all to run a Mac program on a PC.

RAM
RAM is Random Access Memory. It's expensive, high-speed memory that your computer uses as working space. The more you have of it, the larger a program you can run, and the more programs you can run at once. If you have too little, some programs won't run at all. RAM is measured in MB (megabytes).

The hard disk
Almost every computer has a hard disk built into it. If you get a computer without a hard disk, you need to buy an external hard disk for it. A hard disk provides inexpensive, low-speed memory for storage of your data, documents, and programs. Hard disk storage is also measured in megabytes; 250MB is small, 500MB is medium, 1GB (1000MB) is large. You can buy external hard disks as your needs grow.

The floppy drive
Most software comes on diskettes, or "floppies" (so-called because primitive diskettes had a soft envelope, rather than a hard shell). The floppy drive is the thing you shove diskettes into.

All modern Macs take 1.4MB HD (high density) diskettes, but can also use the older, 800K DD (double density) and 400K SD (single density) diskettes. Sufficiently old Macs can't use HD diskettes.

Floppy drives are old technology, and the iMac is the first (and so far the only) computer that doesn't use floppies. Software for the iMac must be on CD-ROMs, or downloaded from the Internet.

Diskettes formatted for a PC can be reformatted for a Mac, and vice versa. You don't have to buy special "Mac" diskettes.

The monitor
The monitor is the screen you look at. If you only use the computer occasionally, a cheap monitor may be OK. If you spend hours staring at the screen, you really need a good monitor, or you'll have problems with headaches and eyestrain.

ROM
You may have heard about ROM (Read-Only Memory). Your computer probably has some. There's nothing you need to know about it. Really.

The keyboard
A keyboard is a keyboard is a keyboard. Some keyboards have a lot of extra keys. Some PC programs require you to use those extra keys. If you have a Macintosh, all those extra keys are pretty useless. You might find a use for some of those keys, but you don't need them. If you really want to put those extra keys to work, buy a program called QuikKeys, which a lot of people really like.

Most keyboards have a numeric keypad, which is convenient if your work requires you to type a lot of numbers. Some keyboards are oddly-shaped to help prevent carpal tunnel syndrome -- they probably help some.

Well-made keyboards have a better "feel" than cheap ones.

The mouse
A mouse for a PC has two or three buttons on top, and different programs use the buttons in different ways. A Macintosh mouse has a single button, and all programs use it the same way.

Unless you buy a fancy optical mouse, you need to open up the mouse and clean it occasionally, whenever the mouse pointer on the screen doesn't seem to move smoothly. A lot of people put up with a jerky mouse because they don't know they need to clean it. Hint: those ridges in the middle of the rollers aren't supposed to be there.

Software
Software is what makes your computer do things. A computer without software is like a VCR without tapes--pretty useless.

The GUI
Once upon a time there were no windows, menus, or mice. The computer put a prompt on the screen, usually A>, and you were expected to type in commands in a special language you had to learn in order to make the computer do anything. (If you have a PC running DOS rather than Windows, it's still this way.) Strictly stone-age stuff.

A GUI (pronounced "gooey"), or Graphical User Interface, provides a much better way: you point at things with the mouse, and click on them. All the commands are on menus, so you don't have to memorize them. This is better for amateurs and professionals alike.

The GUI for Macintosh is called MacOS, and it comes with every Mac. You have a choice of GUIs for the PC, but the one the vast majority of people use is called Microsoft Windows, or just Windows for short.

The printer
The two most popular kinds of printer are ink-jet and laser. Ink-jet printers are very good and inexpensive. Laser printers are excellent and expensive. If you need top quality, get a laser printer. If you can make do with very good quality, get an ink-jet printer. Both Apple and Hewlitt-Packard make great printers for the Mac.

The modem
A modem connects your computer to your phone line, and lets you access other computers and the Internet. The main difference between modems is speed, measured in bps (bits per second). You can get a 14,400 bps modem (also called 14.4) for under $100; anything less is excrutiatingly slow for use with the Internet. The next step up is a 28,800 bps modem, for around $100 or $150. Slightly faster 33,600 bps modems are now available for $150 or $200. Most computers don't yet have these, and when your computer's modem talks to another computer's modem, they talk at the speed of the slower modem. So right now, the extra speed is often wasted--but that's changing fast. Get a 28.8 or 33.6 modem if you can, but 14.4 is still OK.

There are also 56K modems available, but until recently there have been two different incompatible standards. The differences between these have finally been resolved; if you get a 56K modem, get one that meets the new V.90 standard.

The CD-ROM drive
Large programs that require a lot of memory usually come on CDs. A CD-ROM drive lets you use these. Unlike floppy disks, you can read CDs but you can't write them (the RO stands for "read only"). More and more software is being distributed on CD-ROMs, and CD-ROM drives have recently moved from "luxury" to "necessity" status.

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