ls [options] [names]

List contents of directories. If no names are given, list the files in the current directory. With one or more names, list files contained
in a directory name or that match a file name. names can include filename metacharacters. The options let you display a variety of
information in different formats. The most useful options include -F, -R, -l, and -s. Some options don’t make sense together (e.g., -u
and -c).

Linux Commad Options:
-1, --format=single-column
Print one entry per line of output

-a, --all
List all files, including the normally hidden files whose names begin with a period.
-A, --almost-all
List all files, including the normally hidden files whose names begin with a period. Does not include the . and .. directories.
-b, --escape
Display nonprinting characters in octal and alphabetic format.
-B, --ignore-backups
Do not list files ending in ~ unless given as arguments.
-c, --time=ctime, --time=status
List files by status change time (ctime), not creation/modification time. With -l, show ctime and sort by filename; with -lt, show and sort by ctime; otherwise, sort by ctime.
-C, --format=vertical
List files in columns (the default format).
--color[=when]
Colorize the names of files depending on the type of file. Accepted values for when are never, always, or auto.
-d, --directory
Report only on the directory, not its contents; do not dereference symbolic links.
-D, --dired
List in a format suitable for Emacs dired mode.
-f Print directory contents in order, without attempting to sort them.
-F, --classify, --indicator-style=classify
Flag filenames by appending / to directories, * to executable files, @ to symbolic links, | to FIFOs, and = to sockets.
--full-time
List times in full, rather than using the standard abbreviations.
-g Long listing like -l, but don’t show file owners.
-G, --no-group
In long format, do not display group name.
--group-directories-first
Display directories before files.
-h, --human-readable
Print sizes in kilobytes and megabytes.
-H, --dereference-command-line
When symbolic links are given on the command line, follow the link and list information from the actual file.
--help
Print a help message and then exit.
-i, --inode
List the inode for each file.

-I, --ignore pattern
Do not list files whose names match the shell pattern pattern, unless they are given on the command line.
--indicator-style=none
Display filenames without the flags assigned by -p or -f (default).
-k If file sizes are being listed, print them in kilobytes. This option overrides the environment variable POSIXLY_CORRECT.
-l, --format=long, --format=verbose
Long format listing (includes permissions, owner, size, modification time, etc.).
-L, --dereference
List the file or directory referenced by a symbolic link rather than the link itself.
-m, --format=commas
Merge the list into a comma-separated series of names.
-n, --numeric-uid-gid
Like -l, but use group ID and user ID numbers instead of owner and group names.
-N, --literal
Display special graphic characters that appear in filenames.
-o Long listing like -l, but don’t show group information.
-p, --indicator-style=slash
Mark directories by appending / to them.
-q, --hide-control-chars
Show nonprinting characters as ? (default for display to a terminal).
-Q, --quote-name
Quote filenames with "; quote nongraphic characters.
-r, --reverse
List files in reverse order (by name or by time).
-R, --recursive
List directories and their contents recursively.
-s, --size
Print file size in blocks.
-S, --sort=size
Sort by file size, largest to smallest.
--show-control-chars
Show nonprinting characters verbatim (default for printing to a file).
--si
Similar to -h, but uses powers of 1000 instead of 1024.
-t, --sort=time
Sort files according to modification time (newest first).

-u, --time=atime, --time=access, --time=use
Sort files according to file-access time. With -l, show access time and sort by filename; with -lt, show and sort by access time; otherwise sort by access time.
-U, sort=none
Do not sort files.
-v, --sort=version
Interpret the digits in names such as file.6 and file.6.1 as versions, and order filenames by version.
--version
Print version information on standard output, then exit.
-w n, --width=n
Format output to fit n columns.
-x, --format=across, --format=horizontal
List files in rows going across the screen.
-X, sort=extension
Sort by file extension, then by filename.

Examples:

ls -lrt                                               List files by date

ls /usr/bin | pr -T9 -W$COLUMNS         Print in 9 columns to width of terminal

ls -lSr                                               Show files by size, biggest last