With all of the reports, command-line options are useful to modify the
output generated.  These command-line options always occur before the
command word.  This is done to distinguish options from exclusive
regular expressions, which also begin with a dash.  The basic form for
most commands is:

@example
ledger [OPTIONS] COMMAND [REGEXPS...] [-- [REGEXPS...]]
@end example

The @var{OPTIONS} and @var{REGEXPS} expressions are both optional.
You could just use @samp{ledger balance}, without any options---which
prints a summary of all accounts.  But for more specific reporting, or
to change the appearance of the output, options are needed.