Computer systems are composed of more than just a computer (that’s why they’re called systems). A computer houses a hard drive, and is connected to a keyboard, mouse, and video display. All of these hardware devices are required to operate your computer. For most users that’s just the start, you’ll probably have one or more printers, a scanner; maybe even a second monitor. Then of course, there are digital cameras, fax machines... you get the idea.

Computers are made up of a group of hardware devices, and like a conductor at a symphony, Snow Leopard helps you work with those devices, by making the installation, management, and removal easy. In addition, Snow Leopard can help you manage color between devices, help you install MIDI (audio) devices, and even make Internet communications easy. If the worst of the worst problems occur (a system crash), there are steps you can perform to bring your computer system back on line, and you don’t even have to be a techie.

Years ago, hardware installation required all kinds of techniques and special skills. A hardware device such as a printer, could take hours to set up. There were all kinds of cabling problems, and even after it was installed, there were numerous settings to complete before you could use the device. Today, many devices are plug-and-play. You can now go out to your local computer store, pick up a FireWire hard drive, plug it in to your computer, and immediately begin using it. The same is true for many other devices, such as card readers and digital cameras. Even if the device requires the installation of a driver (printers and scanners usually do), a double-click on the install application and answering a few simple questions is typically all that’s needed.

Most hardware devices have settings that control how the device operates. For example, all ink-jet printers have settings that control the type of paper used, how the inks are applied to the paper and, if your printer has more than a single paper tray, which tray is used for the current printing process. Snow Leopard uses the System Preferences panel to display all of the available hardware settings for the major components of the operating system. In addition, when you install specific hardware devices such as a third-party mouse or video-control board, you’ll see an icon for controlling the device in the System Preferences.

When you use any computer, a mouse is an important part of the computing experience. Computers communicate with the user through a series of Graphical User Interfaces or a G.U.I. (pronounced Gooey). The user communicates with the computer through several devices, such as: a touch screen, a keyboard, a drawing tablet and a mouse. Using a mouse requires a bit of hand-to-eye coordination: You see something on the screen (a button perhaps), and you move the mouse pointer over the object and click. Apple understands the importance of the mouse, and gives you ways to control its movement and sensitivity through preferences located in System Preferences. If you have a Bluetooth wireless mouse, you can set it up a new device, check battery levels, and select other Bluetooth-related options.

Your keyboard is another one of those wonderful devices that help us communicate with a computer. Keyboards have what is called a tactile feel (the way the keys bounce back when they’re pressed). Although you can’t control the tactile feel of a keyboard, you can control how the keyboard’s repeat functions work through System Preferences. Keyboard shortcuts allow you to quickly perform a task by pressing keys on your keyboard. You can change or disable many global keyboard shortcuts, the same shortcuts in all applications, to avoid conflicts or customize to suit your own work preferences (New!).

Your monitor is the main interface between you and your computer. A monitor displays all your programs and mouse movements. Without a monitor, you would in fact be attempting to operate your computer with your eyes closed. Apple, in a effort to give you the best possible view of its wonderful operating system interface, gives you the ability to modify how your monitor displays data, through options located in System Preferences.

Have you ever wondered what the exact color value of an item on your monitor would be if measured using RGB (red, green, and blue) values? Or how about the hexadecimal value of a color (useful if you design Web pages)? Color is an important part of any designer’s life, and the Digital Color meter lets you accurately sample colors from your monitor. Since the cursor determines the sampled color, you’ll need to learn a few shortcut keys to lock, print, and save the color information.

The world of color on a computer is a very subjective place to live. For example, you might be using a new Macintosh Studio Display, and someone else might be using a Sony LCD monitor. What this means to you is, a color displayed on your hardware device (monitor) might look slightly different on another computer using a different monitor. In addition, it’s possible that two people, owning the same monitor, may have them adjusted differently. While creating consistent color output is a difficult thing, Mac OS X gives you a stable color picking system, which helps to stabilize colors systems. The Macintosh Color Picker is accessed through an application, such as TextEdit, MS Word or Photoshop, or any application that lets you select colors.

The ColorSync utility gives the designer the ability to match up colors between devices, and to check on and repair the device color profiles present on the computer. As you might have figured out by now, computer monitors are not the best at maintaining color accuracy; especially between monitor and print. The ColorSync utility strives to maintain a color standard between devices, by acting as a translator between different devices. The original scanned image, your monitor, and the output printing device are all examples of where color needs to be synced, and it is achieved though the ColorSync utility.

Macintosh computers were born to work with music, and as the years advanced they got better and better. The Audio MIDI (Musical Instrument Digital Interface) Setup utility is designed to help you setup all your input and output sound equipment, such as microphones, speakers, and multichannel audio interfaces, either built-in or external (New!). In most cases, the default settings work the best. However, if you do work a lot with audio, Apple has made the process of adding, monitoring, and adjusting external devices, such as electronic keyboards and speakers, a snap. If you have multiple audio devices, you can combine them together, known as aggregating devices, to add capacity. For example, if you have an two 6 channel audio devices, you can combine them to work as a single 12 channel audio device.

Whenever you add hardware devices to your computer, the possibility exists that a problem will occur. Problems can fall into several categories: The device doesn’t work, the device doesn’t work the way you expect, or the computer refuses to boot. Apple’s built-in management systems make hardware problems a rare event. However, a few careful steps on your part can help to make problems almost non-existent.

When the worst happens

Sometimes you install a hardware device, and your Macintosh refuses to startup. Many times it’s because you just installed a new hardware device. Unfortunately, when you disconnect the device your Mac still won’t startup. The reason is because the software that runs the device is still installed. When this happens you can attempt a fix by performing a "Safe" boot.

First, you’ll need to power down your computer. After your computer has shut off, go ahead and press the power button. After you hear the startup tone, immediately press and hold the Shift key. You’ll release the Shift key when you see the gray Apple and progress indicator (looks like a spinning gear).

The Safe Mode takes awhile to boot (several minutes). That’s because Safe Mode performs a system check before starting. Then, you’ll use the hardware device’s installation CD to remove the installed hardware. After that is done, restart your computer the normal way (without holding the Shift key).

If removing the device software does not solve the problem, your glitch may be caused by something more serious. You can attempt a reinstall of the OS X operating system, but before doing that, go online and check out the Apple Web site and search for help on your problem. When there is no solution but to start over, or get a new device, you’ll need to remove the hardware device and the software that controls it.

Installing hardware can be relatively easy: you insert the installation CD or DVD and follow the onscreen instructions. However, when you remove a hardware device, the software that ran the device is still on your computer. It’s important to remove any software that is no longer needed for two reasons: it takes up space on your hard drive, and it could cause problems in the future with the installation of other hardware devices.