The advisory line breaking command \linebreak
will produce a line break if it has no argument or if its optional
argument is 4.
The \nolinebreak command is a null command.
The \\ and \\* commands output a <BR> tag,
except inside arrays where the close the current row.
Their optional argument is ignored.
The \newline command outputs a <BR> tag.
All other line breaking commands, declarations or environments are silently ignored.
They are no pages in the physical sense in HTML. Thus, all these commands are ignored.