GNU Emacs Lisp Reference Manual
These functions for parsing words use the syntax table to decide whether a given character is part of a word. See Syntax Tables.
t. If this motion
encounters the beginning or end of the buffer, or the limits of the
accessible portion when narrowing is in effect, point stops there
and the value is nil.
In an interactive call, count is set to the numeric prefix argument.
forward-word, except that it moves
backward until encountering the front of a word, rather than forward.
In an interactive call, count is set to the numeric prefix argument.
This function is rarely used in programs, as it is more efficient to
call forward-word with a negative argument.
forward-word and everything
that uses it. If it is non-nil, then characters in the
``escape'' and ``character quote'' syntax classes count as part of
words. Otherwise, they do not.