In terms of year, every year that Topps produces baseball cards it assigns that year as the primary identifier for that year’s set. For example, cards from the 1985 Topps set are prefixed with “1985” to signify the year. Other card manufacturers may also prefix the year as the primary identifier.

Within each year, cards are further broken down into different sets. Typically the flagship set is the main annual release of cards, but specialty sets focusing on certain themes may also be produced. The flagship set is usually just called something like “1985 Topps Baseball” while specialty sets may be named things like “Topps Traded” or “Topps Rookies” to signify what type of cards are included.

Each set is then given a unique prefix to signify which set it is within that year. So for example the 1985 flagship Topps set would have cards prefixed with “1985T” where the T stands for Topps. Meanwhile a 1985 Topps Traded set may use “1985TT” with the extra T to indicate it’s the Traded set rather than the base flagship set. This set code helps organize cards within a given year.

In addition to or sometimes instead of the year and set code prefix, individual cards themselves are also given sequential serial numbers. These unique card numbers allow for precise identification of a given card separate from the rest. The flagship Topps sets traditionally use a simple sequential numbering from 1 to how ever many total cards are included that year.

For example, the first card in the 1985 Topps Baseball set would be number #1 followed by #2, #3 and so on until the final card of the set is reached. These serial numbers are most commonly printed or stamped directly on the front of the card itself near the player photo or elsewhere easy to find. They help collectors, dealers and enthusiasts verify exact identities.

Sometimes though, specialty subsets like rookie cards or short prints may be unnumbered altogether or have completely different serial schemes compared to the base flagship cards. But generally the flagship annual releases follow a straightforward sequential pattern for their individual card numbers.

Beyond the base identifiers of year, set prefix code and serial number, there are also occasionally additional markings that provide extra detail. Sometimes the card’s specific position in the overall set checklist is annotated. Or parallels and variations that were inserted less frequently may have special serial prefixes.

Overall this detailed system of year – set code – serial number allows for precise tracking and cataloging of the countless baseball cards produced over decades. The numbering helps organize collections and enables quick verification of any given cardboard within the extensive hobby. And it provides reliable at-a-glance information useful for set building, trade, sale and research purposes.