What is chmod symbolic notation?

Chmod symbolic notation uses letters to represent permissions: r (read), w (write), and x (execute). Permissions are grouped into three categories: u (user/owner), g (group), and o (others). Symbolic commands like u+x (add execute for owner) or go-w (remove write for group and others) are often easier to read than their octal equivalents.

# Chmod symbolic notation
chmod u+rwx file     # owner: read + write + execute
chmod g+rx file      # group: read + execute
chmod o-w file       # others: remove write
chmod a+r file       # all: add read
chmod u=rw,g=r,o= file  # owner: rw, group: r, others: none

# Common examples
chmod u+x script.sh      # make script executable
chmod go-rwx secret.key  # owner only access
chmod a+r public.html    # world-readable

Common use cases

System administrators use symbolic chmod to make scripts executable (chmod u+x script.sh), restrict sensitive config files (chmod go-rwx .env), or set group-writable directories for shared projects (chmod g+w /var/www). Symbolic notation is preferred in documentation and automation because it clearly communicates intent without requiring mental octal math.