Pedal and monitor: what they have in common
- Step 1. Pedal — uses — Crank. The pedal sits on a crank: push it and the crank turns the chainring.
- Step 2. Crank — is part of — Arithmometer. The handle for adding and subtracting.
- Step 3. Arithmometer — evolved into — Electronic calculator. Electronics replaced mechanics.
- Step 4. Electronic calculator — has part — Liquid-crystal display. An LCD display.
- Step 5. Liquid-crystal display — is part of — Monitor. Then LCDs.