\pagebreak & \nopagebreak

Synopses:

\pagebreak
\pagebreak[zero-to-four]

or

\nopagebreak
\nopagebreak[zero-to-four]

Encourage or discourage a page break. The optional zero-to-four is an integer that allows you to soften the request. The default is 4, so that without the optional argument these commands entirely force or prevent the break. But for instance \nopagebreak[1] suggests to LaTeX that another spot might be preferable. The higher the number, the more insistent the request. Both commands are fragile (see \protect).

LaTeX’s page endings are optimized so ordinarily you only use this command in a document body to polish the final version, or inside commands.

If you use these inside a paragraph, they apply to the point following the line in which they appear. So this

Four score and seven years ago our fathers brought forth on this
continent,
\pagebreak
a new nation, conceived in Liberty, and dedicated to the proposition
that all men are created equal.

does not give a page break at ‘continent’, but instead at ‘nation’, since that is where LaTeX breaks that line. In addition, with \pagebreak the vertical space on the page is stretched out where possible so that it extends to the normal bottom margin. This can look strange, and if \flushbottom is in effect this can cause you to get ‘Underfull \vbox (badness 10000) has occurred while \output is active’. See \newpage, for a command that does not have these effects.