The usual way to communicate with the computer is to type messages on the computer’s keyboard.

“ move up, to the line above

” move down, to the line below

‘ move left, to the previous character

’ move right, to the next character

When buying a keyboard, you have many choices. You can buy an XT keyboard (83 keys), AT keyboard (101 keys), augmented AT keyboard (101 keys plus an extra copy of the backslash key), or Windows 95 keyboard (101 keys plus 3 special keys that help run software called "Windows 95"). You can buy a standard-size keyboard (with a ledge above the top row, for placing your pencil or notes), compact keyboard (which has no ledge and consumes less desk space), foldable keyboard (which folds in half, as if you’re closing a book, so it consumes half as much desk space when not in use), or split keyboard (whose left third is separated from the rest, so you can have the comfort of typing while your forearms are parallel to each other). You can buy a tactile keyboard (which gives you helpful feedback by making a click whenever you hit a key), silent keyboard (which helps your neighbors by not making clicks), or spill-resistant keyboard (which is silent and also doesn’t mind having coffee or soda spilled on it).

The best split keyboard is the one made by Addison because it’s tactile, requires little pressure, and costs just $50 at Staples discount stores.

Phone Janesway at 800-431-1348 or 914-699-6710.

Method 2: draw on paper, which you then feed to an optical scanner wired to the computer.

Method 3: draw the picture by using a pen wired to the computer. The computerized pen can be a
light pen, touch screen, graphics tablet, mouse, trackball, or joystick.

A light pen is a computerized pen that you point at the screen of your TV or monitor. To draw, you move the pen across the screen.

A touch screen is a special overlay that covers the screen and lets you draw with your finger instead of with a light pen.

A graphics tablet is a computerized board that lies flat on your desk. To draw, you move either a pen or your finger across the board. Modern notebook computers include a tiny graphics tablet (called a touchpad or glidepad), stroked with your finger and built into the keyboard (in front of the SPACE bar).

A mouse is a computerized box that’s about as big as a pack of cigarettes. To draw, you slide the mouse across your desk, as if it were a fat pen.

The mouse was invented at Xerox’s Palo Alto Research Center (PARC). The first company to provide mice to the general public was Apple, which provided a free mouse with every Lisa and Mac computer. Now a free mouse comes with each IBM PC and clone, too.

The nicest mouse for the IBM PC is the Microsoft Mouse. Its first version was boring. Then came an improved version, nicknamed "The Dove Bar" because it was shaped like a bar of Dove soap. It felt great in your hand; but trying to draw a picture by using that mouse — or any mouse — was as clumsy as drawing with a bar of soap. The newest version of the Microsoft Mouse is nicknamed "The Dog’s Paw" because it’s shaped like a dog’s lower leg: it’s long with an asymmetrical bump (paw) at the end. It feels even better than The Dove Bar, unless your hand is too small to wrap around it. Discount dealers sell it for $59. Other brands cost less; the cheapest cost just $10.

A trackball is a box that has a ball sticking out the top of it. To draw, just put your fingers on the ball and rotate it. Some notebook computers have a trackball built into the keyboard.

A joystick is a box with a stick coming out of its top. To draw, you move the stick in any direction (left, right, forward, back, or diagonally) as if you were the pilot of a small airplane.

To produce sounds, the typical computer uses a speaker (similar to the speakers in your stereo system, but smaller).

The speaker is typically inside the system unit. Some computers use the speaker in your TV or monitor instead. The newest computers come with a pair of external stereo speakers, which sit outside the system unit and produce louder sounds. The fanciest new computers come with three external stereo speakers: the third speaker is called the subwoofer and produces a big, loud, booming bass.

Aesthetic computers, such as the Mac, can make speakers play nice music. IBM’s first PC was a boring business computer that produced just harsh beeps, but IBM’s newest computers let you produce sounds as good as a Mac by inserting a sound card (such as the Sound Blaster).

Fancy computers speak words by including circuitry called a speech synthesizer.

The newest computers come with a microphone. By using the microphone, you can make the computer record sounds. For example, you can make the computer record the sound of your voice and imitate it, so the computer sounds just like you!

Turning a computer signal into a telephone signal is called modulating the signal. Turning a telephone signal back into a computer signal is called demodulating the signal. Since the "special device" can modulate and also demodulate signals, the device is called a modulator/demodulator (or modem, which is pronounced "mode em").

The old-fashioned kind is a black box that has big ears on top, so that it can listen to the telephone. Because of its big ears, it’s called a Mickey Mouse modem or an acoustic coupler. It usually costs $120.

The newer kind of modem plugs directly into the phone system, as if it were an answering machine. It doesn’t have any ears: it has telephone wires instead. It’s called a direct-connect modem. It usually costs under $100, and it’s cheaper and more reliable than a Mickey Mouse modem. It’s more popular than a Mickey Mouse modem because it’s better than a Mickey Mouse modem in every way, except that you can’t attach it to pay phones or to phones in hotel rooms.

A direct-connect modem can be either external or internal. If it’s external, it’s a box that sits next to your computer. If it’s internal, it’s a printed-circuit card that hides inside your computer. Regardless of whether it’s external or internal, a wire runs from it to the phone system.

Most direct-connect modems have fancy features, such as auto-dial (which means the modem can memorize the other computer’s phone number and dial it for you) and auto-answer (which means the modem automatically answers the phone whenever the other computer calls). A direct-connect modem having many such fancy features is called smart. Nearly all modems sold today are smart.

The first bit (which is always a 1) is called the start bit; it means "hey, wake up, and get ready to receive the data I’m going to send you". The last bit (which is always a 1) is called the stop bit; it means "hey, I’m done, you can go back to sleep until I send you more data". The eight middle bits (such as 00101110) are usually called the data bits: they’re a code that represents 1 byte of information (1 character). So to transmit 1 character, the modem transmits 10 bits.

A traditional modem transmits 2400 bits per second (2400 bps). That speed is also called 2400 baud. Since 10 bits make a character, that kind of modem transmits 240 characters per second. That speed is reasonably fast: it’s about as fast as the average person can read.

Faster modems can transmit 9600 bits per second (which is 9600 bps, 9600 baud, 960 characters per second). That’s faster than you can read, but it’s appropriate for transmitting documents that you want to skim, programs that you want to run, and graphics.

Even faster modems can transmit 14400 bits per second. Since 1000 bits is called a kilobit, 14400 bits per second is called 14.4 kilobits per second (or 14.4 kbps or 14.4 kilobaud).

All those modems are obsolete. Now the most common speed for transmitting data is 28.8 kilobits per second (which is 28.8 kbps, 28.8 kilobaud).

Most modems sold today can go even faster, 33.6 kilobits per second, but most people using them still transmit at just 28.8 kilobits per second to be compatible with friends using older modems.

Slowing down A few computerists still use ancient, primitive modems transmitting just 1200 bits per second (1200 baud) or 300 bits per second.

To communicate with a friend’s computer, your modem must go at the same speed as your friend’s. For example, if you buy a 33.6-kilobaud modem but your friend has just a 300-baud modem, your modem’s software will detect the slowness of your friend’s modem and automatically downshift (slow down) to 300 baud.

56-kilobaud modems The newest modems claim to go even faster, about 56 kilobits per second (56 kbps, 56 kilobaud), but those claims are misleading!

The government’s Federal Communications Commission (FCC) restricts phone transmissions to 53 kilobaud, to prevent phone switches from overheating. In most communities, the phone companies can’t handle transmissions faster than 45 kilobaud reliably. So if you buy a 56-kilobaud modem, it will probably be restricted to about 45 kilobaud.

Moreover, so-called "56-kilobaud modems" go faster than 33.6 kilobaud just when you’re using the Internet (not when you’re communicating directly with friends), and just when you’re receiving (not sending) Internet data, and just when you’re receiving the data from an Internet service provider that uses the same type of 56-kilobaud modem as yours. (One type of 56-kilobaud modem, called x2, was invented by U.S. Robotics, which makes modems and is now a division of 3Com. The other type, called K56flex, was invented by modem-chip-maker Rockwell and AT&T-spinoff Lucent. The two types are not compatible with each other. A third type is being developed. Most modem makers promise a free upgrade to the third type.)

Standards for modem communication have been invented by AT&T and the International Telecommunications Union (ITU). Here’s what they call their standards:

For example, if you see an ad for a V.22-compatible modem or a Bell 212a modem, the ad is trying to sell you a 1200 bps modem.

Though the ITU speaks English, it used to speak French and have a French name (the Comité Consultatif International Télégraphique et Téléphonique, or CCITT).

Notice that the second version of V.22 is called V.22bis, because bis is a French word that means "2nd version". Notice that the third version of V.32 is called V.32terbo, because terbo is an international word that combines the French "ter" (which means 3) with the English word "turbo" (which means "fast"). Those confusing terms made folks complain that "CCITT" stood for "Committee for Confusing International Telecommunications Terms".

You can send messages from your computer to fax machines around the world, if you buy a fax/modem, which is a modem that can also send faxes. If the fax/modem is fancy, it can also receive faxes and print them on your printer.

The typical modern fax/modem can transmit modem data (to other computers) at 33.6 kilobaud but transmits faxes (to fax machines) at just 14.4 kilobaud. It’s called a 33.6/14.4-kilobaud fax/modem. (Most ads list the modem speed first, then the fax speed, because the modem speed is more important.)

A few years ago, the most common kind of fax/modem was a slow kind that sends modem data at 2400 baud, faxes at 9600 baud. It’s called a 2400/9600-baud fax/modem. More briefly, it’s called a 2496 fax/modem. Yes, every 2496 fax/modem can send faxes at 9600 baud; but the cheapest 2496 fax/modems receive faxes at just 4800 baud — or can’t receive faxes at all!

The most famous modems are made by Hayes, which charges high prices. Other companies make cheaper modems that imitate Hayes’ and are called Hayes-compatible. Nearly all modems sold today are Hayes-compatible.

For example, high-quality Hayes-compatible modems have been built by Everex and Practical Peripherals. To avoid competition from those companies, Hayes sued Everex and bought Practical Peripherals. So Everex had to pay Hayes a royalty (and eventually stopped selling modems), and Practical Peripherals became owned by Hayes.

To pay less for a Hayes-compatible modem, get the ones made by U.S. Robotics or competitors. For example, you can get a U.S. Robotics internal 33.6-kilobaud fax/modem for a net cost of just $56 (after you receive a rebate). You can get a U.S. Robotics internal x2 56-kilobaud fax/modem for $106 (after rebate). Those prices are from a New York discount dealer called Tri State Computer (800-433-5199 or 212-633-2530; ask for David Rohinsky at extension 223).

A modem is an example of a serial device. You might own another serial device also, such as a serial mouse or a serial printer.

The IBM PC can handle two serial devices simultaneously. The first serial device is called communication device #1 (COM1). The second serial device is called COM2.

If the modem is external, run its cable to your computer’s COM2 port. (If your computer doesn’t have a COM2 port yet, buy a serial interface card containing it.)

If the modem is internal, make sure the switch or jumper on the modem is set to the COM2 position; and make sure no other hardware in your computer system is called COM2. For example, if your computer contains a serial interface card having a COM2 port on it, you must disable the serial interface card’s COM2 port (by moving a jumper or switch on it).

Avoid using COM3 or COM4, since the computer has trouble handling COM3 and COM4 reliably. (COM3 often conflicts with COM1, and COM4 often conflicts with COM2.)

Like a disk, a magnetic tape consists of magnetized rust. Just as you put a disk into a disk drive, you put a tape into a tape drive.

Radio Shack You can attach that kind of tape recorder to an old Radio Shack computer (such as the Radio Shack TRS-80 model 1, 3, or 4 or the Radio Shack Color Computer). Wires run from the tape recorder to the computer, and the computer sings a song into the tape recorder; the song is a code that represents the data.

Commodore & Atari Old computers by Commodore and Atari (such as the Commodore Vic, Commodore 64, Commodore 128, and Atari 800) do not attach to ordinary audio cassette tape recorders; you must buy special cassette tape recorders sold by Commodore and Atari or — better yet —buy a disk drive instead, if you can afford it.

Coleco The Adam computer, manufactured by Coleco, comes with a built-in cassette tape recorder, at no extra charge. That tape recorder is high-speed and requires specially lubricated tapes, sold by Coleco. Since it handles just tapes that contain computer information and cannot play ordinary musical tapes, it’s called a digital cassette tape drive instead of an audio cassette recorder. But though Coleco’s tape recorder handles computer data rather well and is called "high-speed", it’s slower than a disk drive.

Colorado The most popular such tape drives have been the Jumbo 120, the Jumbo 250, and the Jumbo 350, all built by Colorado Memory Systems (which used to be an independent company but is now owned by Hewlett-Packard). Those Jumbo drives work with the IBM PC and clones.

The Jumbo 120 can back up a 120-megabyte hard disk by taking the hard disk’s data, compressing it into a shorthand notation, and then storing the compressed data on a 60-megabyte tape. Because of that scheme, the Jumbo 120 is called a 60/120M tape drive.

The Jumbo 250 can back up a 250-megabyte hard disk by compressing the hard disk’s data onto a 120-megabyte tape.

The Jumbo 350 can back up a 350-megabyte hard disk by compressing the hard disk’s data onto a 170-megabyte tape. The drive costs $69. The tapes cost $17 each (in quantity 5).

The newest drives from Colorado are the T1000 (which backs up an 800-megabyte hard disk by compressing onto a 400-megabyte tape, $99 for the drive, $29 for the tape) and the T3000 (which backs up a 3.2-gigabyte hard disk by compressing onto a 1.7-gigabyte tape, $159 for the drive, $30 for the tape).

Ditto Instead of buying a Colorado tape drive, you can pay less by getting a different brand, called a Ditto drive, manufactured by Iomega.

Where to buy You can get Colorado and Ditto drives at those low prices from a New York City discount dealer called Harmony (800-441-1144 or 718-692-3232).

Internal versus external All those tape-drive prices are for drives that are internal: they go inside your computer. External versions cost extra.

Alternatives Instead of buying a tape drive, the typical computerist uses a pile of floppy disks or buys a second hard drive.

Maxicomputers and minicomputers use big reels of tape for three purposes: to backup big disks, to send data by mail, and to store the archives (old files that are used rarely if ever).

To use a reel of tape, you put the reel into a reel-to-reel tape drive, which typically costs about $5000 and writes 1600 bytes per inch, so that the entire tape holds 43 megabytes. Super-fancy drives, used only on the largest maxicomputers, squeeze 6250 bytes onto every inch (instead of 1600), so that they squeeze 171 megabytes onto a single reel of tape.

The motherboard and other main circuitry are enclosed in a box. The box and the circuitry inside it are called the system unit. The box itself — without its contents — is called the case.

The Federal Communications Commission (FCC) prohibits you from owning any device (such as a computer) that interferes with your neighbors’ radio and TV. The FCC requires all computers to pass the FCC class A non-interference test. Any computer used in a residential area must also pass the FCC class B non-interference test, which is harder to pass than the class A test.

When you buy a computer, ask whether it’s FCC class B approved. If it’s not — if it’s just FCC class A approved — you cannot legally use it in a residential area.

Instead of plugging your computer into the wall, you can plug it into a surge suppressor, which is a special extension cord that protects your computer against surges in electrical power.