If you're shopping for a computer this season, think about it the way you'd shop for a car. That means checking out the "sticker" on the retailer's shelf or Web site. Like the sticker on a new-car window, it will list each feature and tell you exactly what you're paying for.
With that in mind, here is my component-by-component breakdown for 2007 shoppers:
Microprocessor: Also known as the CPU (central processing unit), this chip is the part that does the real computing. While there are no slow computers on the market today, a faster processor will do better at running multiple programs simultaneously and handling applications that benefit from raw speed - such as high-resolution gaming or video production.
The vast majority of Windows-based computers and all new consumer Macs use a variant of Intel's Core 2 Duo processor, so named because it combines two processor cores on one chip. A few high-performance models have CPUs labeled Core 2 Extreme or Core 2 Quad (four processors). Most non-Intel processors come from Advanced Micro Devices (AMD). These are compatible with Intel chips.
As a rule, Intel models with higher numbers are more powerful. Also, a processor that runs at higher speed, measured in gigahertz, is likely to perform better than a slower one. Don't sweat small differences. Most manufacturers match the processor to the type of work the machine is advertised to do - so you usually get what you pay for.
Memory: Also known as RAM (short for random access memory), this term refers to the chips that store programs and data temporarily when the computer is running. RAM is measured in gigabytes (GB).
The more memory a PC has, the faster and more reliably it will operate - particularly when you are multitasking, editing photos or video, or playing sophisticated games. To run Windows Vista Home Premium Edition or Apple's new Leopard operating system properly, I recommend 2 gigs of RAM, although low-end models often come with half that much. Upgrade before you leave the store, if possible.
Hard-disk storage: Often confused with memory, the hard disk stores programs and data permanently and shuttles information back and forth into RAM while your PC is running. Hard disk capacity is measured in gigabytes. If you plan on storing lots of video, look for a machine with 250 GB. Otherwise, 120 to 160 GB probably will do - in fact, that's the standard for most off-the-shelf laptops. The good news: external drives that connect to your PC through a USB port are cheap and capacious. Buy one to back up your existing computer, even if you don't need the additional room today.
Video adapter: The video adapter determines what appears on your monitor. For basic computing, the standard video adapter - often manufactured by Intel - will suffice. Remember that these adapters often "share" the computer's main memory, and the sticker will usually note this. Memory sharing can reduce performance.
To get the most from Vista Home Premium and play games at their highest resolution, look for an adapter with at least 128 megabytes of dedicated memory.
Multimedia: With the exception of lightweight laptops, all PCs have some type of compact disk drive. It is used to install new software, back up data and provide entertainment from CDs or DVDs. For maximum flexibility, get one that can read and write DVDs as well as CDs. The ability to create a disk is usually abbreviated with "RW," for read/write. A DVD-RW can create CDs and DVDs. A drive labeled CD-RW/DVD can create CDs but will play only movies or read from DVDs.
Sound: The audio circuits built into most PCs are fine for everyday listening. But music buffs who want the highest fidelity and gamers who need seven-speaker surround sound should look for high-end internal components from Creative Labs, Turtle Beach or specialty vendors.
Monitor: Flat-panel monitors with liquid crystal displays (LCDs) rule the desktop market today, just as they have dominated laptop computing. For a desktop machine, get a 17-inch monitor at minimum, but a 19- or 20-inch screen will make your life easier for as little as $100 extra.
If you are in a store, look for a monitor that is good at distinguishing subtle shades of gray and whose image does not fade when viewed from an angle. If you want to play DVD movies, look for a fast refresh rate that does not smear images during action sequences.
A relatively new issue is the "aspect" or width-to-height ratio of the screen. Laptops and desktop monitors give you a choice. The traditional aspect ratio of TVs, monitors and laptop screens is a squarish 4-to-3. It is best for documents and standard-definition TV shows. So-called "wide-screen" models have an elongated 16-to-9 ratio that is closer to movie screens and high-definition TV broadcasts. Your choice.
Ports: All PCs use universal serial bus (USB) ports to communicate with devices ranging from keyboards and mice to scanners, printers, iPods, cameras, cell phones, external drives and other gadgets. The more USB ports you have, the better. If you're buying a laptop, look for three or more (including one on each side). Better desktop computers have four to six.
Macs and higher-end PCs also have ports labeled FireWire or IEEE 1394 designed for communication with camcorders, external disk drives and other high-speed devices. With fast USB 2.0 technology now universal, FireWire ports are less important today, but useful for older video cameras or specialty equipment.
For convenience, look for a headphone and microphone jack on the computer's front panel as well as the back, particularly if you listen to music or make Internet phone calls.
Another useful accessory is a media reader that can handle various kinds of compact flash memory cards that record images and sound for digital cameras and music players.