UNIX File Permissions

UNIX file permissions control who can read, modify, or execute a file or directory. These permissions are assigned to three groups: the owner (the creator), the group (a set of users), and others (everyone else). Each group has three types of access: read (view content), write (modify content), and execute (run a program or access directory). Permissions are usually represented symbolically (e.g., rwxr-xr--) or numerically (e.g., 754). This system helps ensure that files are protected from unauthorized access while allowing appropriate sharing among users.