If on, Vim will wrap long lines at a character in 'breakat' rather than at the last character that fits on the screen. Unlike 'wrapmargin' and 'textwidth', this does not insert <EOL>s in the file, it only affects the way the file is displayed, not its contents. If 'breakindent' is set, line is visually indented. Then, the value of 'showbreak' is used to put in front of wrapped lines. This option is not used when the 'wrap' option is off. Note that <Tab> characters after an <EOL> are mostly not displayed with the right amount of white space.

(default off)

not available when compiled without the +linebreak feature