1.2. Different Data Models

Consider the humble punch card. Punch cards had been used in France to control textile looms since the early 1700s; the method was perfected by Joseph Marie Jacquard in 1801 with his Jacquard loom.

Flash forward to the year 1890, when a man named Herman Hollerith invented a punch card and tabulating machines for that year’s United States Census. His census project was so successful that Mr. Hollerith left the government and started the Tabulating Machine Company in 1896. After a series of mergers and name changes, this company became IBM. You might have heard of it.

Up to the 1970s, the “IBM card” and related machinery was everywhere. The most common card was the IBM 5081, and that part number became the common term ...

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