\\[*][space]: break line, not justification; \\* version does not allow new page after use; space indicates optionally how much space before next line
\-:word may be hyphenated at this point
\cleardoublepage: as for \clearpage but insures next page is odd, perhaps creating a blank even page if necessary.
\clearpage: ends current page and prints out all pending figures and tables
\hyphenation: list of words separated by spaces with allowable hyphenation points within words indicated by dash (-)
\linebreak[number]: break line at current point (or request with increasing strength with number 0 to 4) and stretch line to justify.
\newline: break line where it is, do not justify
\newpage: new page right now
\nolinebreak[number]: prevents breaking the current line at the point of the command. Can make it a request with strength increasing from number 0 to 4.
\nopagebreak[number]: prevent breaking current page at the point of command, with optional nicety argument as above
\pagebreak[number]: break page at the point of the command, with optional nicety argument as above.
\allowbreak: especially useful to allow breaks within an inline equation after a comma, which is not normally allowed