Horizontal space in lists

Question

What is the best way to change the amount of horizontal space in list environments?

Examples:

1.############################ % Near the enumerated item - compacted horizontal space
  ############################

2.############################
  ############################

3.############################
  ############################

and

1.     ############################ % Far from the enumerated item - stretched horizontal space
       ############################

2.     ############################
       ############################

3.     ############################
       ############################

Answer 1

You can adjust all list parameters easily using the enumitem package. For the example you give, the relevant parameter is the labelsep key:

\documentclass{article}
\usepackage{enumitem}
\begin{document}
\begin{enumerate}[labelsep=5em]
\item foo
\item bar
\end{enumerate}
\end{document}

For other parameters, check the documentation or look for other questions on the site that use the enumitem package.

Answer 2

Without using any package, you can use list as follows.

\documentclass{article}


\usepackage{lipsum}
\begin{document}


\noindent
\lipsum[1]

\begin{list}{\stepcounter{enumi}Problem \arabic{enumi}:\ }
{
\setlength{\labelwidth}{2cm}
\setlength{\labelsep}{1cm}
\setlength{\leftmargin}{3cm}
}
   \item \lipsum[2]
   \item \lipsum[3]
\end{list}

\end{document}