I switched batteries in my computer. They are EXACTLY the same but one's

Question

but one's "current power source:" is ac power, the other is dc power. How is this possible? Did I somehow push some button that told my computer to operate on ac or dc power? What is the difference anyway when it concerns laptops? (I know what ac and dc stand for and how they work, so if some psuedo intellectual wants to give the acronym's direct meaning please just don't answer. Because that is not the question. If I wanted to know that I could just type it in wikipedia.)

Answer 1

On all of our laptops, when it says "Current power source AC" that means that it is currently plugged into the wall and is running off of outlet power. It only switches to DC when the power supply is unplugged or disconnected and it automatically switches over to battery power. If it gets plugged back in, it switches back to AC power.