Herman Hollerith applies for US patent #395,781 for the 'Art of Compiling Statistics', which was his punched card calculator.

Herman Hollerith was a German-American statistician, inventor, and businessman who developed an electromechanical tabulating machine for punched cards to assist in summarizing information and, later, in accounting. His invention of the punched card tabulating machine, patented in 1884, marks the beginning of the era of mechanized binary code and semiautomatic data processing systems, and his concept dominated that landscape for nearly a century.

A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention. In most countries, patent rights fall under private law and the patent holder must sue someone infringing the patent in order to enforce their rights.

A punched card is a stiff paper-based medium used to store and process digital or analog information through the presence or absence of holes in predefined positions. Developed from earlier uses in textile looms such as the Jacquard loom (1800s), the punched card was first widely implemented in data processing by Herman Hollerith for the 1890 United States Census. His innovations led to the formation of companies that eventually became IBM.

An electronic calculator is typically a portable electronic device used to perform calculations, ranging from basic arithmetic to complex mathematics.