Spreadsheet and pneumatic tube: what they have in common
- Step 1. Spreadsheet — uses — Personal computer. It ran on the Apple II.
- Step 2. Personal computer — has part — Microprocessor. The PC became possible thanks to the microprocessor.
- Step 3. Microprocessor — is part of — Anti-lock braking system (ABS). A control unit.
- Step 4. Anti-lock braking system (ABS) — evolved from — Air brake. Anti-skid systems first appeared in aviation and on railways.
- Step 5. Air brake — uses — Compressed air. The brake is controlled by air pressure in the train pipe.
- Step 6. Compressed air — is used in — Pneumatic tube. Air pressure.