Punched paper, the player piano and the first programs

A music box plays a tune that someone wrote down as holes or pins: a row for each note, low to high, and a column for each beat. Turn the handle and every hole that passes the comb plays its note. CrankPals is one of these, on paper.

In 1804 the French weaver Joseph Marie Jacquard built a loom run by a chain of punched cards. A hole meant lift this thread; no hole meant leave it. Change the cards and the same loom wove a different pattern.

Around 1900, player pianos played music from long paper rolls with holes punched in them. Air rushing through a hole pressed that key. Many homes had one, and famous pianists recorded rolls so that people could hear them play.

The same idea ran the first computing machines. In the 1830s Charles Babbage planned an engine that would take its instructions on punched cards, and in 1843 Ada Lovelace wrote that it would weave algebraic patterns as the Jacquard loom weaves flowers and leaves. She also wrote that such an engine might one day compose music. In 1890 the United States counted its census on Herman Hollerith's punched-card machines.