To the OP: Yes
Using the battery will not exactly damage it, but it's a consumable. It is designed to maintain a decent charge for about 1000 charge cycles.
On the other hand, not using the battery is also bad, and can actually damage it (e.g. leaving it fully discharged for extended periods of time can kill it).
It's like with a car. If you use it, you have to replace a few parts (tires, oil) after certain thresholds. However, if you don't use it, some stuff might still break, e.g. the car battery.
The bottom line is that you should use the laptop the way it is most convenient for you, and not worry about the battery. Also, read the FAQ, but of course nobody ever does that, otherwise the forum would be pretty empty!