The WiFi wireless networking standard does a good job at broadcasting its radio frequency signal throughout most buildings.
Both
802.11b and the faster
802.11g WiFi equipment have a range of about 100 feet.
This range extends both horizontally and vertically, so the wireless signal can travel to an upstairs bedroom or basement office.
Naturally, the further away you get from the main transmitter (that is, the wireless router), the weaker the signal becomes. At its most extreme range, a weak signal will translate into slower transfer speeds and intermittent connections.
If you're having trouble connecting your PC to your
wireless network, try moving the PC closer to the base station. Alternately, you can install a
WiFi extender in your home.
A wireless extender (sometimes called a "repeater") receives the original WiFi signal and then "repeats" it from the new location, in effect extending the range of the original signal. Extenders are available from
D-Link,
Linksys,
U.S. Robotics and other networking equipment manufacturers.
Michael Miller is a writer and commentator on technology and digital lifestyle topics. 
