$ help history
history: history [-c] [-d offset] [n] or history -anrw [filename] or history -ps arg [arg...]
    Display or manipulate the history list.

    Display the history list with line numbers, prefixing each modified
    entry with a `*'.  An argument of N lists only the last N entries.

      -c        clear the history list by deleting all of the entries
      -d offset delete the history entry at position OFFSET.

      -a        append history lines from this session to the history file
      -n        read all history lines not already read from the history file
                and append them to the history list
      -r        read the history file and append the contents to the history
      -w        write the current history to the history file

      -p        perform history expansion on each ARG and display the result
                without storing it in the history list
      -s        append the ARGs to the history list as a single entry

    If FILENAME is given, it is used as the history file.  Otherwise,
    if HISTFILE has a value, that is used, else ~/.bash_history.

    If the HISTTIMEFORMAT variable is set and not null, its value is used
    as a format string for strftime(3) to print the time stamp associated
    with each displayed history entry.  No time stamps are printed otherwise.

    Exit Status:
    Returns success unless an invalid option is given or an error occurs.
$ shopt -p | grep -i hist
shopt -s cmdhist
shopt -s histappend
shopt -u histreedit
shopt -u histverify
shopt -u lithist
$ shopt | grep hist
cmdhist         on
histappend      on
histreedit      off
histverify      off
lithist         off
$ shopt -o | grep -i hist
histexpand      on
history         on