What are "permissions"?

[superspiffy]

As a recent switcher from the world of Windows, what are permissions and what does repairing permissions actually do?

 

[jsw]

Permissions specify who (which accounts) can do what to each file - read it, write it, run it, etc. They're like the "Security" tab items when you get the Properties of a file in Windows.

Sometimes they get out of whack, and repairing them ensures the right accounts can do the right things to each of the files.