Saw this question on the apple website regarding battery, "Does it harm the battery or reduce battery life, to use the AC adaptor for extended periods while the battery is fully charged?" Someone answered, "I would have to disagree with the others who say that it hurts your battery & reduces battery life by keeping your AC adapter plugged in with a full battery. I have done extensive research and asked many apple employees and have always come to the same conclusion. They all say to keep your laptop plugged into an power supply whenever possible. Only use your battery if you have to, in those times when you are not near a power supply. Every time you use your batteries power you are adding to the amount of cycles your battery can cycle. If you continually charge your battery to 100% and then take it off the AC Power, and use it all the way down to 0% or even 50% you are taking away from the batteries lifespan. And eventually your battery will not be able to hold a full charge, and eventually will not hold a charge at all, and you will have to buy a new one! Use your AC Power as much as you can, but remember to calibrate your battery at least once a month to maintain proper battery health." I would just like to know whether this is true. Because i have been recharging every time, even when i'm at home. I'm afraid that keeping the AC adaptor on at all times will harm and reduce the battery life.