The landmark 1989 Upper Deck Baseball is a 800-card set released in two series. The first series (also known as the "Low-Numbers") consists of the first 700 cards, and was released to The Hobby in April 1989. The High-Number Series, which has both the 700 Low-Number cards, plus an additional 100 cards, was released in October.
The cards feature slick paper stock, full color on both the front and the back and carry a hologram on the reverse to protect against counterfeiting.
1989 Upper Deck is notable, of course, for card #1: The Star Rookie of Ken Griffey, Jr. Other rookies included Gary Sheffield, John Smoltz, Randy Johnson (all, like Griffey, included in the "Star Rookie" subset) Craig Biggio. Among the Hi-Series rookies are Tom Gordon, Steve Finley, Jim Abbott and Omar Vizquel.