If I change a file in my local ubuntu One directory:
- Will it be sync to the cloud server?
- Will this file be updated on another PC's ubuntu one directory ?
Ubuntu One allows synchronization of files across machines and does this by synchronizing any file you put in the ~/Ubuntu One folder.
Yes, Ubuntu one automatically syncs files in your local directory with the files in cloud.
This will only happen, if you or someone logged in to that PC and Ubuntu one service starts.