When your files are saved in OneDrive, you can access them from any device, even if something happens to your PC. You can go to the OneDrive website, or you can use a mobile app for Android, iOS, or the Windows Phone.
Accessing files when you’re offline
On Windows 8.1, you can browse all your files in OneDrive even when you're not connected to the Internet. If you also want to open and edit files when you don't have Internet connection, you need to make those files available offline. You can use the OneDrive app or File Explorer to make files available offline.