IBM's punch cards were the first modern data storage medium, marking it as a pioneer in the data processing industry. Their origins reside in the late 19th century, when Herman Hollerith, a statistician working on the 1890 U.S. Census, devised a system of punched paper cards to encode and process data more efficiently than manual counting. His invention created a foundation for more advanced data processing. In fact, his company, the Tabulating Machine Company, would later merge into International Business Machines (IBM) in 1924. Under IBM’s leadership, punch cards transitioned into a universal tool for information storage, enabling multiple job sectors to manage vast amounts of data.

By the 1920s and 1930s, IBM had refined Hollerith’s system, introducing the standardized 80-column punch card. These stiff, rectangular sheets of paper were filled with tiny punched holes, and served as the primary means of processing data. They quickly became an industry staple, whereby entire industries began to rely on them. For example: banks used punch cards for financial records, corporations for payroll and inventory management, and government agencies for census data and military logistics.

During World War II, punch cards played a critical role in wartime computing and codebreaking. The US military used IBM's punch card for cryptography and weapons development, including calculations for the Manhattan project. The punch card was a critical technology in the early stages of the atomic bomb. Across the globe, in Nazi Germany, the government also controversially used IBM’s punch card technology to organize administrative records, including tracking populations during the Holocaust.

By the 1950s, as computers began to replace mechanical tabulators, IBM punch cards remained integral to data processing. Early electronic computers, including the IBM 650 and IBM 1401, still relied on punch cards for data input. In the era of mainframe computing, these cards became the primary interface between human operators and machines. FORTRAN, COBOL, and assembly language programs were often written on decks of punch cards, with programmers submitting stacks of them to computer operators, feeding the cards into readers.

The 1960s marked both the peak of IBM punch card usage and the beginning of its decline. Computers like the IBM System/360, introduced in 1964, still supported punch cards, but alternative input methods, such as magnetic tape and disk storage, began gaining traction. Punch cards, while reliable, were slow to process and required significant manual handling. Workers spent hours feeding stacks of cards into machines, and a single misplaced or damaged card could disrupt an entire program or dataset.

By the 1970s, the decline of punch cards accelerated. Interactive computer terminals and keyboards allowed users to input and modify data directly, removing the need for physical cards. Other storage materials provided more efficient ways to store information. Companies that once depended entirely on punch card processing no longer needed to rely on it, transitioning to digital databases and preliminary networked computing.

IBM, in 1984, ceased the production of punch card equipment, forcing punch cards' inevitable decline. However, their influence on modern computing remains undeniable. The concept of structured, machine-readable data storage pioneered by punch cards provided a basis for modern databases and programming logic. Even today, the 80-character width of many programming languages and text editors is a direct legacy of IBM’s punch card format.

The Manhattan Project

Originating back to the US Census of 1980, Herman Hollerith's punch card solved the issue of manually tabulating census data. This system, brilliant in its own right, replaced handwritten calculations and increased processing speed eightfold, reducing the time required from eight years for the 1880 Census to just one year for the 1890 Census. This innovation was particularly notable because it laid the foundation for modern data processing, eventually prompting the creation of IBM.