Sandpaper and Babbage’s Analytical Engine: what they have in common

1. Step 1. Sandpaper — is made of — Paper. The backing.
2. Step 2. Paper — is material for — Punched card. Punched cards are stiff card.
3. Step 3. Punched card — is used in — Babbage’s Analytical Engine. Operations and numbers were entered on punched cards.

Open Evothings