The ability to assign enforceable permissions to files and folders is part of the NTFS file system. If you assign NTFS permissions, you need to understand how they work and how they are different for a file and for the folder that contains the file.
What Permissions Mean
NTFS permissions affect access both locally and remotely. Share permissions, on the other hand, apply only to network shares and don’t restrict access on the part of any local user (or terminal server user) of the computer on which you’ve set the share permissions. Windows 2008 Server has a set of standard folder permissions that are combinations of specific kinds of access. The individual permissions are Full Control, Modify, Read & Execute, List Folder Contents, ...