What are the file permissions and access modes in Unix?

There are three types of permissions – owner, group and other (public), all of which can be listed using the command ls -l. Each user can have one or more of the following access – read (r), write (w), execute (x). Example, -rwxr-xr-- represent the file permissions for owner, members and everyone else as –

• Characters 2-4 (rwx) – means the owner has read, write and execute permission,
• Characters 5-7 (r-x) – indicates that the group has read and executed permission,
• Characters 8-10 (r--) – indicates that everyone else has only read permissions.