Hard back book: 'Baseball's 100' by Maury Allen (1981)

High Numbers - vintage cards were issued in the ‘50s-‘70s in a series. During the baseball season, the largest number of cards were made. As the schedule progressed into September, when there would be less interest in baseball cards , Topps for one, specifically decreased production and hence much less product was available. As a result, a scarcity-factor was created and a premium holds for these first type of "short-printed" cards.

Inserts - special randomly-inserted cards which are not part of the regular set. Many modern inserts are sequentially-numbered and rarer than the card sets into which they are inserted.

O-Pee-Chee / OPC - a subsidiary of Topps, this card issue was produced specifically for distribution in Canada.

Promotional Card - generally referred to as cards issued to show what the product will look like on release and intended to help spur future sales. Often called a "promo" card.

Reprint - cards issued to reproduce the originals. With the current trend of vintage reprints, the new versions have a distinguishing characteristic evidenced by numbering.

Restored - a card or piece of memorabilia which someone has tried to return to a "like-new" condition. A restored card is considered to be of very little value.

Rookie Card - any league-licensed, widely distributed card to feature a player in his first year of trading cards.