Direct Current (the variety that we get from a battery) can go only one way or another- positive or negative. As a result, the length of the wire it travels in causes a great deal of resistance, wasting energy, and a short anywhere in a DC circuit can destroy the whole thing.
Alternating Current goes both ways, travels effeciently over long wires, and should a short occur, only a small portion of the total gets damaged.
Direct Current was advocated by Edison as a power distribution system, AC by Tesla.
If you _think_ about it, this makes sense. Really. I swear.