Think of the battery in your laptop as a car's gas tank. You can use the car while the gas pump is plugged in and filled up, or you can use the gas that's already in it for a while. When you plug in, power keeps coming in, which is great for long work sessions or hard jobs. However, the battery lets you move around and work from any spot, like that nice swing under the tree. The important thing is that it won't hurt your laptop to use it while it's charged. These days' computers are smart enough to control how they charge and keep them from getting damaged.
