Electrical wiring, meaning of the term "hots"
While it's not a perfect analogy, think of this in terms of a kitchen sink (yes, I am throwing a kitchen sink at the question). 


The faucet - It's hooked to a pipe that brings water in so you can use it
The drain - A pipe hooked to something that takes water away. 


You then interface with the water within the sink.

In your circuit (because electricity requires one to work), you have the same basic thing.


Hot wire - Typically black, this carries current in from your power company. This is your "faucet"
Neutral wire - Carries electricity away to some sort of electrical sink (in most cases, the ground on the main service box). This is your "drain"
Ground - Think of this as a wet/dry vacuum for when your kids play in the kitchen sink and spill water everywhere. Ground soaks up everything that should have gone down the drain but didn't. Since you dump your wet/dry vac down the drain when you're done, it all goes to the same place eventually.


Why do we call it "hot"? Because it burns (sometimes literally) if you touch it while it's energized. It also might lead to dancing, colorful metaphors and other bad things