Four-In-A-Row

This is a simple version of the well known game that goes by a variety of names, including "Four In A Row".
The system will not let you make a move until each piece has finished dropping, or let you add a piece to a column that is already full. No warning is given in either case, since these should both be obvious. A version that you can play against the computer will follow shortly.

Player Names:
Yellow (first move):
Red: