The IBM punched card
The paper on-ramp to the Information Age once held most of the world’s data
Close-up of a punched card with an Olympic logo on it, and the words VIII Olympic Winter Games, California 1960

It was one of the earliest icons of the Information Age: a simple punched card produced by IBM, commonly known as “the IBM card.” The card itself was unassuming, a thin piece of stiff cardboard measuring 7⅜ inches by 3¼ inches comprising 80 columns, 12 rows and a series of tiny rectangular holes. But for almost half a century, IBM cards held most of the world’s stored data.

The punched card preceded floppy disks, magnetic tape and the hard drives of later computers as the first automated information storage device, increasing efficiency and speed, and significantly lowering the risk of human error involved in recordkeeping by hand. The punched card provided a significant profit stream for IBM and helped propel the company to the forefront of data processing.

As late as the mid-1950s, punched card sales made up roughly 20% of IBM’s revenue and 30% of its bottom line. Along the way, the IBM card also became a cultural icon, a powerful symbol of 20th-century automation that came with a catchphrase warning: “Do not fold, spindle or mutilate.”

The evolution of punched cards
From looms to the US census

Punched cards, also known as punch cards, dated to the late 18th and early 19th centuries when they were used to “program” cloth-making machinery and looms. In the late 1880s, inventor Herman Hollerith, who was inspired by train conductors using holes punched in different positions on a railway ticket to record traveler details, invented the recording of data on a machine-readable punched card. Hollerith’s cards were used for the 1890 US Census, which finished months ahead of schedule and under budget. Punched cards emerged as a core product of what would become IBM more than two decades later.

IBM introduced the “IBM Computer Card” in 1928 as the result of a secretive competition between the company’s two top research teams. Over the following three decades, IBM and its rivals redesigned the cards using different sizes and greater numbers of holes with each representing a bit of data. Around 1900, punched cards featured 22 columns and eight punch positions; then 24 columns and 10 positions; until the late 1920s, they had 45 columns of round holes and 12 punch positions.

Data was assigned to the card by punching holes, each one representing a character, in each column. When writing a program, one card represented a line of code — about 80 bytes in total — so large stacks of the cards were required. To load the program or read punched card data, each card would be inserted into a punched card reader to input data into a tabulating machine.

As demand for storage continued to grow, the card soon ran out of room and couldn’t get any larger. To solve this problem, Thomas J. Watson Sr., head of IBM at the time, asked two of his top inventors, Clair D. Lake and J. Royden Pierce, to each develop a new card that held more data. They were instructed to work independently, and only one design would be chosen.

Pierce wanted to use IBM’s existing card with round holes, but make it possible for each hole to represent more than one number or symbol — thereby doubling storage capacity, with half devoted to alphanumeric characters. Lake’s team proposed a card with smaller rectangular holes, which would be easier to read by tabulators. This idea, however, would require new punchers and readers.

Watson asked James W. Bryce, IBM’s most prolific inventor, to choose the best solution. Bryce voted for Lake’s approach because it could be implemented quickly and required the least adjustment in how tabulating machines worked. There were business advantages as well — Lake’s card would double the amount of data stored and be compatible only with IBM-manufactured machines. Introduced in 1928, the new IBM card had 80 columns and 10 rows for coding numbers, then 12 in a modified version of the card unveiled in 1930.


The Social Security Administration
A launching point for punched cards

The IBM card won broad acceptance and served as a model for other special-purpose cards and hardware products. During the United States New Deal, IBM’s punched cards were used not only in the tabulation and recordkeeping of government contracts but also to print government-issued checks. The 1935 Social Security Administration contract required millions of IBM punched cards and tabulating machines to process data and print checks.

IBM’s Fred M. Carroll developed a series of high-speed rotary presses that revolutionized the company’s production of punched cards. By 1937, IBM had 32 presses at work in Endicott, New York, printing, cutting and stacking 5 million to 10 million punched cards every day.

Over the decades, the IBM card had countless uses across industry and society. Police stored and managed criminal records with them, libraries could better track books, and utility companies sometimes printed bills directly onto them. Until the early 1990s — long after IBM had ceased selling punched cards for data processing — it was common practice for IBMers to jot notes on them for their presentations.

The IBM card was replaced by more advanced storage technologies such as magnetic tape, which delivered both a faster method of data processing and greater storage capacity. Tape was also far more compact compared with the massive stacks of punched cards needed to process data. But the IBM card will always be remembered as a transformative technology and an essential part of IBM’s development. For nearly half a century, thin pieces of cardboard with tiny rectangular holes made the world quantifiable.

For nearly half a century, thin pieces of cardboard with tiny rectangular holes made the world quantifiable
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