Performance
Features that affect the performance of the computer include:

• microprocessor - Pentium, Celeron, AMD, or G4
• operating system - Windows (98, 2000, NT) or Mac OS
• RAM
• disk drives - hard, floppy, Zip, CD, DVD
• display - color vs. monochrome, active vs. passive
• battery - lithium, nickel-cadmium, nickel-metal hydride
• input/output ports - parallel, serial , USB
• fax/modem - internal vs. external
• sound cards and speakers

Microprocessors
Like standard desktops, laptops are powered by microprocessors. The microprocessor is the brain of the laptop and coordinates all of the computer's functions according to programmed instructions (i.e. the operating system software). For Apple Macintosh users, the choice of microprocessor is limited. Most Powerbooks and iBooks are equipped with Motorola's G3 version of the PowerPC family, although some high-end Powerbooks can have the G4 microprocessor. For PC users, there is a wider variety. You can choose from Intel's Pentium and Celeron families or AMD's K5 and K6 families. Pentium III microprocessors tend to be found in high-end laptops, whereas Celeron and AMD chips tend to be found in lower-end models. The choice between these chips depends upon your needs for speed versus cost. Click here for a discussion of the differences between Pentium and Celeron chips.

Operating Systems
The operating system is the set of pre-programmed instructions that tells the microprocessor what to do. Operating systems on laptops include Windows 98/2000/NT (Microsoft) and Mac OS, depending upon the type of computer (PC vs. Mac); some systems can be loaded with Linux, although this is not an option for most consumers. You may also want to consider that the latest operating system (e.g. Windows 2000 or Windows NT) may not be the best one for your laptop. Operating systems vary in their use of power management, security encryptions (in case your laptop is stolen) and cost. See the Links section for information regarding the best operating system for your notebook computer.

RAM
With all of the options out there, you may be wondering how much memory you need in your laptop. You should probably buy a laptop with a minimum of 64 MB RAM. Also, check to see how much VRAM you have, because this will be important in running graphics (minimum = 2 MB VRAM). Some laptops allow you to upgrade memory, and may have an easy access panel that provides for convenient switching of memory chips. In other upgradeable laptops, you have to open the case to get under the keyboard to add memory, or send it to a repair technician.

Disk Drives
Like desktops, laptops have various disk drive storage devices. All laptops have an internal hard disk drive, usually 6 to 20 GB. You will have fewer choices in hard disk drives in a laptop than you would in a desktop model, but 10 GB is a reasonable storage capacity. In addition to hard drives, most laptops have some type of removable disk storage system, such as floppy disks, Zip disks, compact disks (CD) and digital video disks (DVD). There are three options for disk drives in laptops:

• Some laptops have more than one bay built into the case for disk drives (such as a floppy drive or a CD-ROM drive).
• Some laptops have one bay that you can swap or interchange various drives. You just pull one drive out and put another in:
  • "cold-swappable" drive - You must turn the computer off, change drives, and then reboot the computer.
  • "hot-swappable" drive - You can change the drives without turning the computer off. This feature saves you the time involved in restarting the computer.
• Some laptops have no internal drives. All drives are external and connected to the computer by cables. This feature allows the laptop to be very small and thin.

• from 12 to 15 inches
• black-and-white (16 grayscale) or color (65,536 colors)
• passive or active matrix - active matrix displays have sharper images and are easier to read
• reflective or backlit - backlit screens are good for low-level room lighting conditions
• 800 x 600 pixel resolution or less.

Large screen sizes, active matrix and backlighting make a better display, but also increase the price of the computer. A 13- to 14-inch, active matrix, color screen is worth the investment, though, especially if you plan to search the Internet often or make multimedia presentations using your laptop. The screen should have 800 x 600 pixel resolution or higher for clear, crisp displays. You needn't settle for a resolution of 640 x 480 pixels because the higher resolution is fairly standard now.

Batteries
To make laptops portable, they are powered by batteries. All laptops use some type of rechargeable battery (lithium, nickel-cadmium, nickel-metal hydride). The battery life varies, depending upon the type of rechargeable battery (lithium batteries tend to hold their charge longer and have no memory effect) and how you use your computer (frequent use of disk drives consume a lot of battery power). A battery should have a minimum life of 2 hours; of course, 4 hours is even better. Many laptop computer models have power management software to extend the battery life, or conserve battery power when the battery is low; power management software may be built into the operating system. You may notice that as your battery gets low, your laptop runs slower. This effect is typically the result of internal power management software, and indicates that you should plug in the computer's AC adapter, or quit and re-charge your battery. Laptops can be plugged into the wall to re-charge the battery, or can be connected directly to AC power through an AC adapter. Laptop computer batteries can cost from $50 - $250 depending upon the type of battery and computer. If you travel frequently, especially if you travel long distances, then you may want to consider buying an extra battery.

Input/Output Ports
Computers need to talk to other devices (e.g. printers, modems, networks). Computers send and receive information through various input/output ports which can include serial ports, parallel ports and Universal Serial Bus (USB) ports. At minimum, you should have a printer port, which is usually a parallel port, and one or two USB ports. In addition to ports, some laptops have expansion slots for PCMCIA standard adapter cards (Type I and Type II) or "PC " cards. These cards can be used to upgrade your laptop by adding memory, a modem, a network connection or a peripheral device. A PC card slot will help extend the life of your laptop by allowing you to upgrade rather than replace your laptop in the future. You may want to look for a docking station port on your computer. The docking station was invented to make the laptop more convenient for desktop use. The docking station has several peripheral devices (full-size computer monitor, full-size keyboard, mouse, disk drives, printer) connected to it. You just plug your laptop into the station, and you're ready to use it as a desktop computer; in other words, you make one connection to your laptop instead of many. Most laptops have a docking connection.

Fax/Modem
If you have to communicate with your company or customers while on the road, access e-mail, fax documents or access the Internet, you will need a modem. Look for a laptop with an internal fax/modem with a minimum of 56 kps. This will allow you to send and receive information by just hooking up to a phone connection. If your laptop does not have an internal fax/modem, you may be able to add one through a PC card slot.

Sound Cards and Speakers
Like desktops, most laptops are equipped with sound cards and speakers so they can play music from CDs. However, the quality of the speakers built into most laptops does not match that of speakers for desktops, because space is a major limitation in a laptop case. If your laptop has no sound equipment, you can add it through a PC card slot. If sound quality is important to you, you can upgrade it by using external speakers.