AirPort Extreme card. how does it work?

An Airport card in your iBook would make it wireless. To receive a wirless signal you need the Airport card in your iBook and you have to be around somewhere where you can get the signal. A wireless router takes the ethernet from your cable or DSL modem and broadcasts it to a range with luck of maybe 200 feet. So if you have a wireless router in your house, you can be wireless. Your iBook will also pick up other wireless signals which are around. A good freeware software item is called Macstumbler. It will identify the signals nearby, their strength and if they are pword protected. Many places provide the signal free like some coffeeshops, McDonalds, airports, motels etc. If you have your iBook in your car and drive through a neighborhood of college student rentals, you can find maybe 40 wireless networks, 1/3 of which have no pwords. An Airport card will not allow you to pick up a signal while driving unless you are in a city that provides wifi for free or you are in a parking lot for McDonalds etc. You would need to connect the iBook to a cell phone to go wireless if you are not near a wirless router base station. All iBooks have the slot for an Airport card, it is easy to install. Just check the Apple website.