Linux.com: CLI for Noobies: Mother, May I?

“There are few things as confusing, frustrating, and aggravating
for those who come to Linux from Windows as the whole notion of
permissions. Based on my own personal experience, I would say as
much as 25% of the problems I’ve had using Linux over the years
have been permissions related. It’s a subject your mother didn’t
teach you, and you didn’t learn on the playgrounds. That’s why
we’re going to get down and dirty with the CLI today: to learn
about permissions on Linux, right here, right now.

“Permissions are flags which control who can do what with a
file. Which file? Any file on your system. For each file, there are
three separate flags which indicate whether or not you can read a
file, write a file, or execute a file. Just because you can do one,
doesn’t mean you can do the other two.

“Permissions are necessary for security. Because Linux is truly
a multiuser system, it needs to protect each user’s data from all
the other users…”

Complete
Story