\frame{ \frametitle{}
 \hspace{1em}
 \begin{centering}
 \hspace{-1cm}\includegraphics[height=3cm]{cactuslogo}\\
 \Huge Examples\\
 \end{centering}
}

\frame[containsverbatim]{ \frametitle{Hello World, Standalone}
 Standalone in C:
 \begin{verbatim}
  #include <stdio.h>
  int main(void)
  {
    printf("Hello World!\n");
    return 0;
  }
 \end{verbatim}
}

\frame[containsverbatim]{ \frametitle{Hello World Thorn}
 \begin{itemize}
  \item \verb|interface.ccl|:
   \begin{verbatim}
   implements: HelloWorld\end{verbatim}
 \item \verb|schedule.ccl|:
  \begin{verbatim}
   schedule HelloWorld at CCTK_EVOL
   {
     LANG: C
   } "Print Hello World message"\end{verbatim}
  \item \verb|param.ccl|: empty
  \item \verb|REAME|: \tiny
   \begin{verbatim}
      Cactus Code Thorn HelloWorld
      Author(s)    : Frank Löffler <knarf@cct.lsu.edu>
      Maintainer(s): Frank Löffler <knarf@cct.lsu.edu>
      Licence      : GPL
      --------------------------------------------------------------------------

      1. Purpose

      Example thorn for tutorial Introduction to Cactus
\end{verbatim}
 \end{itemize}
}
\frame[containsverbatim]{ \frametitle{Hello World Thorn cont.}
 \begin{itemize}
  \item \verb|src/HelloWorld.c|:
   \begin{verbatim}
    #include "cctk.h"
    #include "cctk_Arguments.h"

    void HelloWorld(CCTK_ARGUMENTS)
    {
      DECLARE_CCTK_ARGUMENTS
      CCTK_INFO("Hello World!");
      return;
    }\end{verbatim}
  \item \verb|make.code.defn|:
    \begin{verbatim}
     SRCS = HelloWorld.c\end{verbatim}
 \end{itemize}
}

\frame[containsverbatim]{ \frametitle{Hello World Thorn}
 \begin{itemize}
  \item parameter file:
   \begin{verbatim}
    ActiveThorns = "HelloWorld"
    Cactus::cctk_itlast = 10\end{verbatim}
  \item run: \verb|[mpirun] <cactus executable> <parameter file>|
 \end{itemize}
}

\frame[containsverbatim]{ \frametitle{Hello World Thorn}
 \begin{itemize}
  \item Screen output:\tiny
   \begin{verbatim}       10                                  
  1   0101       ************************  
  01  1010 10      The Cactus Code V4.0    
 1010 1101 011      www.cactuscode.org     
  1001 100101    ************************  
    00010101                               
     100011     (c) Copyright The Authors  
      0100      GNU Licensed. No Warranty  
      0101                                 

Cactus version:    4.0.b17
Compile date:      May 06 2009 (13:15:01)
Run date:          May 06 2009 (13:15:54-0500)
[...]

Activating thorn Cactus...Success -> active implementation Cactus
Activation requested for 
--->HelloWorld<---
Activating thorn HelloWorld...Success -> active implementation HelloWorld
--------------------------------------------------------------------------------
INFO (HelloWorld): Hello World!
INFO (HelloWorld): Hello World!
[...] 8x
--------------------------------------------------------------------------------
Done.
   \end{verbatim}
 \end{itemize}
}