One of the most widely used specifications, the resolution refers to the maximum number of dots per inch (dpi) that can be printed, measured both horizontally and vertically. For example, a 600 x 600dpi laser printer lays down a one-inch square composed of 600 dots across by 600 dots down. In theory, a printer with a higher resolution is capable of producing more-detailed text and images, as seen in this representation:
Though manufacturers have inflated the numbers for marketing purposes, and the numbers no longer correlate directly with higher image quality, resolution still has some bearing on the quality of text and curves, especially on premium papers.

This spec measures how many pages per minute (ppm) a printer spits out. Sounds pretty straightforward, right? Unfortunately, it's not so simple. To come up with the fastest-possible speeds, some manufacturers test using basic text documents at the lowest-quality print settings (Draft mode) on plain paper--not exactly a real-world test. Based on our experience, you can expect to see about half the speed promised by the manufacturer.

The USB (Universal Serial Bus) is truly universal--all printers have either a USB 1.1 or the newer, faster USB 2.0 port. The two standards get along just fine but if you want better performance, look for a printer which supports at least the high-speed USB 2.0 interface. Mac users can also opt for models that feature the FireWire (IEEE 1394) interface. And if you want to go old school, you'll still find plenty of printers that accept those big, 25-pin parallel cables. Workgroup printers also support printing over a network using a standard Ethernet cable with an RJ-45 connector. For even better mobility, many models support printing wirelessly, using infrared, Bluetooth, and Wi-Fi access points with built-in print servers.

Nearly all manufacturers provide information on the processor and the memory, but at least for personal use, these specs are relatively unimportant. Your computer does a fine job, largely on its own, of lining up print jobs and sending them on to be printed. If you have multiple users or you often print high-resolution photos or other large files, however, then you'll want a printer with a faster processor and more onboard memory.

More advanced paper-handling features--such as tabloid-size printing, duplexing (printing on both sides), and auto document feeders for faxing and copying--will be found on only higher-end models, though they're beginning to trickle down to everyday consumer models as well.