Punched Card Data Processing
Punched Card Data Processing
Punched cards were a revolutionary technology that allowed data to be stored and processed mechanically or electronically through a series of holes punched into cards. Used extensively throughout the 20th century, punched cards were instrumental in the development of early computing and data processing technologies. The use of punched cards transformed industries such as census data collection, industrial manufacturing, and government record-keeping.
Historical Background
The origins of punched card technology can be traced back to the late 18th century with the development of the Jacquard loom, which used punched cards to control the weaving of textiles. This concept was adapted for data processing by Herman Hollerith in the 1890s for the 1890 U.S. Census. Hollerith's innovation allowed census data to be encoded on punched cards, drastically reducing the time required for data tabulation.
Evolution of Punched Card Systems
Punched card systems evolved over time, with companies like IBM playing a pivotal role in standardizing the format. The IBM 80-column punched card became the industry standard for data input, storage, and output. These cards were used in unit record machines, which were organized into data processing systems capable of performing various operations like sorting, tabulating, and calculating.
Punched Card Equipment
Various machines were developed for use with punched cards, including:
- Tabulating Machines: These machines could perform complex calculations by processing cycles of punched cards.
- Card Readers: Devices that read information from punched cards and transferred it to computing systems.
- Sorters: Machines designed to organize decks of punched cards based on the data encoded on them.
- Tape Punches: Equipment that could transfer data from punched cards to punched paper tapes for further processing.
Impact on Computing
The use of punched cards was not limited to data processing; they also played a crucial role in early computer programming. Programmers would encode instructions line by line on individual punched cards, forming the basis of software programs. This method of programming was used well into the era of mainframe computers.
Transition to Electronic Data Processing
By the mid-20th century, electronic data processing technologies began to replace punched card systems. However, the legacy of punched cards is evident in modern information processing systems, which owe much of their development to the innovations in data processing technologies initiated by punched cards.