Todo Notes
Todonotes is a way to allow visual note items in your compiled LaTeX document The notes can be customized for different colors and themes to correspond to different topics/categories and can be placed in-line, in the margins, and even be used as placeholders for figures that have not yet been added.
% Documentation
\todo{this is my todo note}
\todo[inline]{here is an inline todo note}
\todo[background=red]{a note with a different background color}