Installing a light fixture - Where does the red wire connect to?

I am trying to install a light fixture. It turns on by a light switch on the wall. It is not a dimmer switch, just an average light switch. There never was a fixture there to begin with. The electrician installed the wall switch for me but did not install the the fixture. He said I could do it myself with no problem. From the ceiling, there are four wires (black, white, red and a copper wire) My light fixture has three wires ( black, white and green). I know that the green and the copper are ground, so they go together. I know black to black and white to white. But there is this extra red wire. Does it piggy back with the black wires? Do I just cap it off?.