Sky Diver for the Atari 2600 is essentially a game of chicken.
Sky divers exit the plane with the fire button, whereby they enter free-fall. In free-fall, they plummet rapidly toward the earth and will squish into the ground if the parachute isn't pulled. When and if, the parachute is pulled, the diver can then control his or her direction of descent, as mitigated by the wind direction and wind speed. When the parachute is pulled, the descent speed is naturally slowed, but this can be at a player's disadvantage when, as in some games, there is but one target to land on for both players.
There are a total of 9 jumps in a game, and each jump can score a maximum of 11 points. Points are earned by landing on the target that is either color-coded or is shared by both players. The later the parachute is pulled, the higher the score is. Wait too long to pull the parachute, though, and the sky diver will squish into the ground with a wet, crunching sound. While missing the target with the parachute pulled is zero points, cratering decreases a player's score by 4. No points are awarded for cratering in the target area.
The ultimate challenge can be found in one of the game options where there is one target shared between the players. The strategy is that if a player holds off pulling his or her chute longer than the other player, then he or she will land on the target first. Only the diver who reaches the target first (and is still alive) gets any points for the jump. If you hold off too long the parachute won't open, and you'll make a permanent impact on the landscape.
There are other options, such as moving targets and an absence of wind, and the difficulty switches alter the size of the targets.