Wi-Fi standards can be a confusing, ever-changing subject, especially when manufacturers engage in a war of buzzwords regarding the latest frivolous features. You can safely ignore most of those marketing terms--especially ones that are trademarked. With that out of the way, let's look what you do need to know to choose a wireless router, configure a network, and get started.
Select a Wireless Router
These days, you should buy a router that uses the 802.11n wireless standard. But there are a few caveats. This Wi-Fi protocol is backward-compatible with 802.11g and 802.11b; if you or a visitor uses a laptop based on one of those older technologies, the machine will work with your new router so long as you configure the router for backward compatibility. The 802.11n spec reaches farther and transfers data faster than the other two Wi-Fi methods; nevertheless, it has not yet received official approval as a standard.
The final 802.11n specifications are expected to appear in 2010, so technically you'll be buying a draft 802.11n router. There's a very small chance that current routers won't work with the final standard; but since the companies that sit on the 802.11n decision board have been selling their versions of those chips, they are unlikely to rock the boat much at this point. Instead, a free firmware release will likely update today's routers to the final approved specification.
It's a good idea to choose a dual-band router. Such routers divide traffic over two areas of the wireless spectrum, 2.4GHz and 5GHz. This arrangement basically opens up an extra lane for communications so the network can handle more data at once, and at faster speeds. Many routers, such as the Linksys Simultaneous Dual-N Band Wireless Router (WRT610N), can divide traffic over two SSIDs (service set identifiers--aka network names), letting you put slower or lower-security 802.11b devices on their own loop. Other routers, such as the Netgear Rangemax Dual Band Wireless-N Gigabit Router (WNDR3700) let you isolate traffic on the two wireless networks. This is ideal for leaving an open segment as a neighborly gesture, while closing off file sharing to your PCs.
You should base the remainder of your buying decision on the router's ports. Even though theoretically you could set up a wireless-only system, your network will likely consist of a mixture of wired and wireless devices. Wired connections are still optimal for speed, simplicity, reliability, and security.
Many wireless routers still include 100Base-T ethernet, instead of the speedier gigabit (1000Base-T) standard. Look for a model that incorporates the higher gigabit speed so that your network can keep wired traffic blazing along. Even while streaming high-definition video around your home, you'll be able to share other files without a slowdown. For maximum benefit you'll have to use gigabit ethernet computers, but you could upgrade your 100Base-T clients subsequently, since they (and 10Base-T clients) still work with faster hardware. Routers commonly include about four ethernet ports. Get more if you need them (and if you can)--or see my instructions at "Use a Switch to Add More Ports," to increase the number later on.
Some routers include a USB port, too. Consult the documentation for the specific model you're considering purchasing for details of its use; typically, you can connect the USB port to a printer or hard drive to bring those devices onto the network. If those features match your needs, the extra cost is justified. If not, focus on the abilities discussed earlier.
If range is crucial in your setup, be sure to get a router that has an external antenna port, and don't naively rely on the broadcast distance advertised on the packaging. Many factors influence a router's range, including the structure of the surrounding building and interference from neighbors. If you're trying to blanket an entire house--or backyard--you miay have to buy a second access point.