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Shared is like a user, but everyone can access the files stored there. The Public folder is under a specific user and allows that user to control other people's access to it. It contains things like the Drop Box where people can add files to your account, but they can't see what's in there.
 
Other users on your computer or anyone who can connect to your computer on a network...

Some teachers use it as a way for their students to submit homework assignments. Students can just drag a file into the teachers Drop Box, and the teacher can see them all right there in one folder.
 
but still don't understand about public folder,,,who can add stuff to it??? what u mean ppl can add stuff???

You can put stuff in your public folder youself and other users can read it, but other people can't delete, change or add stuff.

Other people can drop things to you in the drop-box. Only you can see what's been dropped.

Everyone can read and write to the shared folder. It's basically free for all.
 
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