store data on punched cards is vendor specific. In general each column represents a single digit, letter or special character. Sequential card columns allocated for a specific use, such as names, addresses, multi-digit numbers, etc., are known as a field. An employee number might occupy 5 columns; hourly pay rate, 3 columns; hours worked in a given week, 2 columns; department number 3 columns; project charge code 6 columns and so on. Keypunching Original data were usually punched into cards by workers, often women, known as keypunch operators, under the control of a program card (called a drum card because it was installed on a rotating drum in the machine), which could automatically skip or duplicate predefined card columns, enforce numeric-only entry, and, later, right-justify a number entered. Their work was often checked by a second operator using a verifier machine, also under the control of a drum card. The verifier operator re-keyed the source data and the machine compared what was keyed to what had been punched on the original card. Sorting An activity in many unit record shops was sorting card decks into the order necessary for the next processing step. Sorters, like the IBM 80 series Card Sorters, sorted input cards into one of 13 pockets depending on the holes punched in a selected column and the sorter's settings. The 13th pocket was for blanks and rejects. Cards were sorted on one card column at a time; sorting on, for example, a five digit zip code required that the card deck be processed five times. Sorting an input card deck into ascending sequence on a multiple column field, such as an employee number, was done by a radix sort, bucket sort, or a combination of the two methods. Sorters were also used to separate decks of interspersed master and detail cards, either by a significant hole punch or by the cards corner-cut. More advanced functionality was available in the IBM 101 Electronic Statistical Machine, which could Sort Count Accumulate totals Print summaries Send calculated results (counts and totals) to an attached IBM 524 Duplicating Summary Punch. Tabulating Reports and summary data were generated by accounting or tabulating machines. The original tabulators only counted the presence of a hole at a location on a card. Simple logic, like ands and ors could be done using relays. Later tabulators, such as those in IBM's 300 series, directed by a