futuristic remote control
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Could this remote control program your entire house?
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When you're not home, nagging little doubts can start to­ crowd your mind. Did I turn the coffee maker off? Did I set the security alarm? Are the kids doing their homework or watching television?

With a smart home, you could quiet all of these worries with a quick trip online. When you're home, the house takes care of you by playing your favorite song whenever you walk in or instantaneously dimming the lights for a movie. Is it magic? No, it's home automation. Smart homes connect all the devices and appliances in your home so they can communicate with each other and with you.

Anything in your home that uses electricity can be put on the home network and at your command. Whether you give that command by voice, remote control or computer, the home reacts. Most applications relate to lighting, home security, home theater and entertainment and thermostat regulation.

The idea of a smart home might make you think of George Jetson and his futuristic abode or maybe Bill Gates, who spent more than $100 million building his smart home [source: Lev-Ram]. Once a draw for the tech-savvy or the wealthy, smart homes and home automation are becoming more common. About $14 billion was spent on home networking in 2005, and analysts predict that figure will climb to more than $85 billion by 2011 [source: Regan].

Inside Bill Gates' Home
Microsoft Chairman Bill Gates' home just outside of Seattle, Wash., might be the most famous smart home to date. Everyone in the home is pinned with an electronic tracking chip. As you move through the rooms, lights come on ahead of you and fade behind you. Your favorite songs will follow you throughout the house, as will whatever you're watching on television. You can entertain yourself by looking at Gates' extensive electronic collection of still images, all available on demand. The chip keeps track of all that you do and makes adjustments as it learns your preferences. When two different chips enter the same room, the system tries to compromise on something that both people will like.

Why are smart homes becoming more popular? Are they easy to operate? And why did that light just turn off behind me? On the next page, we'll take a look at the technology in a smart home.