generell gilt: was du nicht auf anhieb weisst, kannst du ( meistens) in den manuals nachlesen.
und zwar in der konsole - dort gibt man "man befehlsname" ( zum beispiel "man ls" ohne anfuehrungszeichen) ein, und erhaelt erstaunliches...
"NAME
ls - list files and/or directories
SYNOPSIS
ls [ options ] [ file ... ]
DESCRIPTION
For each directory argument ls lists the contents; for each file argument the name and requested information are listed. The current directory is listed if no file arguments appear. The listing is sorted by file name by default, except that file arguments are listed before directories.
Multi-column terminal output display width is determined by ioctl(2) and/or the COLUMNS environment variable. [...]"