List information about directories and files, the current directory by default.
# To list files one per line:
ls -1
# To list all files, including hidden files:
ls -a
# To list all files, with trailing '/' added to directory names:
ls -F
# To long format list (permissions, ownership, size, and modification date) of all files:
ls -la
# To long format list with size displayed using human readable units (KiB, MiB, GiB):
ls -lh
# To long format list sorted by size (descending):
ls -lS
# To long format list of all files, sorted by modification date (oldest first):
ls -ltr
# To only list directories:
ls -d */