A PATTERN is a string of characters that specifies  a  set  of
        possible  strings  of  characters  that  are said to MATCH the
        pattern.  Most characters in patterns  stand  for  themselves,
        but   there   are   metacharacters:   "?"   that  matches  any
        character, "*" that along with the previous character, matches
        any number of repetitions of  it  (including  none),  "%"  for
        beginning  of  line,  "$"  for  end of line, and characters in
        brackets "[]" to match any of  the  characters.   The  special
        sense  of  metacharacters  and  of the delimiters in which the
        pattern is enclosed can always be  turned  off  by  preceeding
        them with the escape character "@".

        See also "hs", "hg", "hx" for uses of patterns.
        For the use of patterns in line numbers, type "hscan".
        For examples of pattern matches, type "hpatex".