diff --git a/doc/doxygen/pages/input-output.md b/doc/doxygen/pages/input-output.md
index 067a8165db75dc56114a18f3bd64afdb55c69516..8e1a206dd859d476021ea4392a5ffe7643caa927 100644
--- a/doc/doxygen/pages/input-output.md
+++ b/doc/doxygen/pages/input-output.md
@@ -198,14 +198,50 @@ The example above is taken from `test/porousmediumflow/1pnc/implicit/1p2c/noniso
There is support for reading data and grids from VTK files, see Dumux::VTKReader.
## Gnuplot interface
-DuMux provides a small interface to GNUPlot, which can be used to plot results and generate
-image files (e.g., png). To use the gnuplot, gnuplot has to be installed.
-For more information see Dumux::GnuplotInterface.
+DuMux provides a small interface to [Gnuplot](http://www.gnuplot.info/),
+which can be used to plot results and generate
+image files (e.g. `.png`). To use the gnuplot, gnuplot has to be installed.
+The following is a brief introduction. For the class documentation, see Dumux::GnuplotInterface.
+
+A Gnuplot interface is available to plot or visualize results during a simulation run.
+To use the gnuplot interface you have to make some modifications in your file, e.g., your main file.
+
+First, you have to include the corresponding header file for the gnuplot interface.
+
+```cpp
+#include <dumux/io/gnuplotinterface.hh
+```
+
+Second, you have to create an instance of the class
+Dumux::GnuplotInterface (e.g. called `gnuplot`).
+
+```cpp
+Dumux::GnuplotInterface<double> gnuplot;
+```
+
+As an example, to plot the mole fraction of nitrogen (`y`) over time (`x`),
+extract the variables after each time step in the time loop.
+The actual plotting is done using the method of the Gnuplot interface:
+
+```cpp
+gnuplot.resetPlot(); // reset the plot
+gnuplot.setXRange(0.0, 72000.0); // specify xmin and xmax
+gnuplot.setYRange(0.0, 1.0); // specify ymin and ymax
+gnuplot.setXlabel("time [s]"); // set xlabel
+gnuplot.setYlabel("mole fraction mol/mol"); // set ylabel
+// set x-values, y-values, the name of the data file and the Gnuplot options
+gnuplot.addDataSetToPlot(x, y, "N2.dat", options);
+gnuplot.plot("mole_fraction_N2"); // set the name of the output file
+```
+
+It is also possible to add several data sets to one plot by calling Dumux::GnuplotInterface::addDataSetToPlot more than once.
+For more information have a look into a test including the gnuplot interface header file, the class documentation
+of Dumux::GnuplotInterface, or the header file itself `dumux/io/gnuplotinterface.hh`.
## Container I/O
DuMux supports writing to file from and reading
into some STL containers like `std::vector<double>` or `std::vector<Dune::FieldVector>`.
-If you want to read and write simple vectors, have a look at the header dumux/io/container.hh.
+If you want to read and write simple vectors, have a look at the header `dumux/io/container.hh`.
## Matrix and Vector I/O
diff --git a/doc/handbook/0_dumux-handbook.tex b/doc/handbook/0_dumux-handbook.tex
index 2011035f7f1a5492d19c4bde4579fc1639800a85..97cddbd418fc8ec4f39aceaca792523e50f7d74e 100644
--- a/doc/handbook/0_dumux-handbook.tex
+++ b/doc/handbook/0_dumux-handbook.tex
@@ -127,7 +127,6 @@ concepts (\ref{sc_linearsystem}).
\input{5_newfoldersetup}
\input{5_restartsimulations}
\input{5_developingdumux}
-\input{5_externaltools}
\input{5_scripts}
\input{5_assemblinglinearsystem}
diff --git a/doc/handbook/5_externaltools.tex b/doc/handbook/5_externaltools.tex
deleted file mode 100644
index 903f266b598abb5b2da825b858967e58ba4ff8f7..0000000000000000000000000000000000000000
--- a/doc/handbook/5_externaltools.tex
+++ /dev/null
@@ -1,73 +0,0 @@
-% SPDX-FileCopyrightInfo: Copyright © DuMux Project contributors, see AUTHORS.md in root folder
-% SPDX-License-Identifier: CC-BY-4.0
-
-\section{External Tools}
-\label{sc_externaltools}
-
-\subsection{Git}
-Git is a version control tool which we use.
-The basic Git commands are:
-\begin{itemize}
- \item \texttt{git checkout}: receive a specified branch from the repository
- \item \texttt{git clone}: clone a repository; creates a local copy
- \item \texttt{git diff}: to see the actual changes compared to your last commit
- \item \texttt{git pull}: pull changes from the repository; synchronizes the
- repository with your local copy
- \item \texttt{git push}: push committed changes to the repository; synchronizes
- your local copy with the repository
- \item \texttt{git status}: to check which files/folders have been changed
- \item \texttt{git gui}: graphical user interface, helps selecting changes for
- a commit
-\end{itemize}
-
-
-\subsection{Gnuplot}
-\label{gnuplot}
-A gnuplot interface is available to plot or visualize results during a simulation run.
-This is achieved with the help of the \texttt{Dumux::GnuplotInterface} class provided in \texttt{io/gnuplotinterface.hh}.
-
-To use the gnuplot interface you have to make some modifications in your file, e.g., your main file.
-
-First, you have to include the corresponding header file for the gnuplot interface.
-\begin{lstlisting}[style=DumuxCode]
-#include <dumux/io/gnuplotinterface.hh
-\end{lstlisting}
-
-Second, you have to define an instance of the class \texttt{Dumux::GnuplotInterface} (e.g. called \texttt{gnuplot}).
-\begin{lstlisting}[style=DumuxCode]
-Dumux::GnuplotInterface<double> gnuplot;
-\end{lstlisting}
-
-As an example, to plot the mole fraction of nitrogen (\texttt{y}) over time (\texttt{x}),
-extract the variables after each time step in the time loop.
-The actual plotting is done using the method of the gnuplot interface:
-
-\begin{lstlisting}[style=DumuxCode]
-gnuplot.resetPlot(); // reset the plot
-gnuplot.setXRange(0.0, 72000.0); // specify xmin and xmax
-gnuplot.setYRange(0.0, 1.0); // specify ymin and ymax
-gnuplot.setXlabel("time [s]"); // set xlabel
-gnuplot.setYlabel("mole fraction mol/mol"); // set ylabel
-
-// set x-values, y-values, the name of the data file and the Gnuplot options
-gnuplot.addDataSetToPlot(x, y, "N2.dat", options);
-
-gnuplot.plot("mole_fraction_N2"); // set the name of the output file
-\end{lstlisting}
-
-It is also possible to add several data sets to one plot by calling \texttt{addDataSetToPlot()} more than once.
-For more information have a look into a test including the gnuplot interface header file, the doxygen documentation
-of \texttt{Dumux::GnuplotInterface}, or the header file itself (\texttt{dumux/io/gnuplotinterface.hh}).
-
-
-\subsection{Gstat}
-Gstat is an open source software tool which generates geostatistical random fields (see \url{www.gstat.org}).
-In order to use gstat, execute the \texttt{bin/installexternal.py} from your \Dumux root
-directory or download, unpack and install the tarball from the gstat-website.
-Then, rerun cmake (in the second case set \texttt{GSTAT\_ROOT} in your input file to the
-path where gstat is installed).
-
-
-\subsection{ParaView} \label{ssec:paraview}
-To visualize the simulation data you have produced using \Dumux, we recommend using \href{https://www.paraview.org/}{Paraview}.
-This open-source software supports \Dumux~'s standard data formats, and can be operated either with a GUI or with batching tools.
\ No newline at end of file