Why does Dropbox take up space on my hard drive?

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Tags

1. #storing
2. #choose
3. #running
4. #files
5. #default
6. #folder
7. #dropbox
8. #drive
9. #selective
10. #space
11. #computer
12. #actively
13. #using
14. #about
15. #folders
16. #archival
17. #worry
18. #never
19. #great
20. #which