\documentclass[a4paper,ngerman,12pt]{article} 
\usepackage[T1]{fontenc} 
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\usepackage{rotating}
\usepackage{url}
\usepackage{babel}

\title{Eine Tabellendemonstration}
\author{Erasmus von Rotterdam\thanks{%
    \protect\url{hvr@amsterdam.nl}}%
    \and Herbert Voß\thanks{%
    \protect\url{voss@perce.de}}%
}
\date{\today}
\begin{document} 
\maketitle

\noindent
\resizebox{\linewidth}{!}{%
\begin{tabular}{|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|}\hline
& \rotatebox{90}{Write}  & \rotatebox{90}{Mode} & \rotatebox{90}{Block}& \rotatebox{90}{Network} &
  \rotatebox{90}{Access} & \rotatebox{90}{Read} & \rotatebox{90}{Disk} & \rotatebox{90}{Device}  &
  \rotatebox{90}{Directory}&\rotatebox{90}{Time}& \rotatebox{90}{Data} & \rotatebox{90}{File}    &
  \rotatebox{90}{Structure}&\rotatebox{90}{Interface} & \rotatebox{90}{Software} &
  \rotatebox{90}{Type}   & \rotatebox{90}{Version} & \rotatebox{90}{Systems} & \rotatebox{90}{Program} &
  \rotatebox{90}{Command}& \rotatebox{90}{Memory} & \rotatebox{90}{Root} & \rotatebox{90}{Process} &
  \rotatebox{90}{Page}   & \rotatebox{90}{Address}\\\hline
I/O Services&X&X&X&X&X&X&X&X&X&X&X&X& & & & & & & & & & & & & \\\hline
System Call Interface& & & & & & & & & & & & &X&X&X&X&X&X&X&X& &X& & \\\hline
Process Scheduler& &X& & & & & & & &X& & &X& & & & & & & & & &X& & \\\hline
Interprocess Communication& & & & & & & & & & &X& & & &X& & &X&X& & & &X&&\\\hline
Memory Management&X&X&X& &X&X& &X& & &X& & & & & & & & & &X& & &X&X\\\hline
\end{tabular}
}

\end{document}
