Why do planes fly in a curved path?

Related questions

1. Are you allowed to fly over Antarctica?
2. What is the great circle route method?
3. Why is great circle the shortest distance?
4. How does the great circle route work?
5. Why do planes fly over Greenland when crossing the Atlantic?
6. How do airplanes communicate over the ocean?
7. Do planes fly over Tibet?
8. Why do planes not fly over Antarctica?
9. Could penguins survive in the North Pole?
10. What determines flight paths?

Tags

1. #between
2. #flight
3. #shortest
4. #lines
5. #rather
6. #distance
7. #constant
8. #straight
9. #called
10. #because
11. #heading
12. #curved
13. #circle
14. #those
15. #nothing
16. #sphere
17. #route
18. #points
19. #rotation
20. #earth
21. #great