Hint: Technology
The answer to this puzzle is:
1. ENGINE
2. WHEEL
3. FLIGHT
4. WEBCAM
5. CIRCUIT
6. COMPUTER
7. ROCKET
8. KEYBOARD
9. TEXTING
10. PROGRAM
11. SCANNER
12. RADIO
13. FAX
2. WHEEL
3. FLIGHT
4. WEBCAM
5. CIRCUIT
6. COMPUTER
7. ROCKET
8. KEYBOARD
9. TEXTING
10. PROGRAM
11. SCANNER
12. RADIO
13. FAX