\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=1.3}

\begin{document}
\pgfplotsset{
    small,
    every axis plot post/.style={
        fill=orange!75,
        draw=orange!50!black
    },
 %   trim axis left
}

\begin{tikzpicture}
\begin{axis}[ymin=0,title=\texttt{hist}]
\addplot [hist] table [y index=0] {plotdata/pgfplots.randn.dat};
\end{axis}
\end{tikzpicture}\hfill
\begin{tikzpicture}
\begin{axis}[ymin=0, title=\texttt{hist=density}]
\addplot [hist=density] table [y index=0] {plotdata/pgfplots.randn.dat};
\end{axis}
\end{tikzpicture}\vspace{1cm}

\begin{tikzpicture}
\begin{axis}[ymin=0, title=\texttt{hist=cumulative}]
\addplot [hist=cumulative] table [y index=0] {plotdata/pgfplots.randn.dat};
\end{axis}
\end{tikzpicture}\hfill
\begin{tikzpicture}
\begin{axis}[ymin=0, title=\texttt{hist=\{cumulative,density\}}]
\addplot [hist={cumulative,density}] table [y index=0] {plotdata/pgfplots.randn.dat};
\end{axis}
\end{tikzpicture}
\end{document}

