What is a "Overfull \hbox (9.89561pt too wide)"?

Question

I have this warnings around, some of them seems to be solved naturally but I never really understand what do they mean.

What this means?

Edit: I would like to keep the question in more general terms, but in this particular case the source code related to this warning is the following:

\item {\bf Finalização} onde são finalizados os histogramas, eventualmente traçadas curvas de ajuste \emph{(fit)} e guardados os resultados no disco.

Possible duplicate: This question solves the debug issue of this.

PS: Sorry if this question is quite newbie.

Answer 1

The allowed space between two words is given by the interwordspace (\fontdimen2\font) and interwordstretch (\fontdimen3\font). If it is not possible to set a paragraph with these lengths (with hyphenation) TeX will complain with a overfull or underfull box. Setting the \emergencystrech to a value greater than 0pt it can stretch the interwordspace to a bigger value. You can set this value individually or using \sloppy or the environment sloppypar

\documentclass[draft]{article}
\usepackage[textwidth=4.5cm]{geometry}
\usepackage{blindtext}
\parindent=0pt
\begin{document}
interwordspace: \the\fontdimen2\font \\

interwordstretch: \the\fontdimen3\font \\

emergencystretch: \the\emergencystretch\par
\blindtext

\newpage
\begin{sloppypar}
interwordspace: \the\fontdimen2\font \\

interwordstretch: \the\fontdimen3\font \\

emergencystretch: \the\emergencystretch\par
\blindtext
\end{sloppypar}

\end{document}

Answer 2

for my case, the easiest solution that I found is to add \begin{sloppypar} after \maketitle and to add \end{sloppypar} at the end of my document. It worked like charm: I don't have any text going out of the columns anymore. My document tex looks like:

\begin{document}
% title + keywords + abstract 
\maketitle
\begin{sloppypar}
% document body
\end{sloppypar}
\end{document}