I'm creating a Beamer presentation and I wanted to change margin size for single slides. I've found a solution on some old mailing list, adapted it a little and it works perfectly, but I have no idea how it works=/
\newenvironment{codemargin}{%
\begin{list}{}{%
\setlength{\leftmargin}{-0.7cm}%
\setlength{\rightmargin}{-0.7cm}%
}%
\item[]}{
\end{list}
}
This creates a new environment that I can use on slides that I want to have smaller margins.
Now to the point - what does \item[]}{ mean? I can't find any other examples using similar syntax.