Screen reader and refrigerator: what they have in common
- Step 1. Screen reader — evolved from — Braille. Access to text for blind people.
- Step 2. Braille — works like — Binary number system. Six dots — a six-bit code.
- Step 3. Binary number system — is used in — Barcode. The bars encode digits.
- Step 4. Barcode — is used in — Supermarket. Barcodes.
- Step 5. Supermarket — uses — Refrigerator. Refrigerated displays.