==== Kinds of model documentation ====

  * Formulation: Describes the theory that constitutes the model.
    * What is encoded in the model?
    * How is this derived from a more general theory?
    * Equations and discretization methods

  * Implementation: Describes the practical realization of the model
    * Model components and the related programming units: modules and routines, input and output variables, configuration parameters
    * Flow chart / calling graph
    * External data: if needed, units, formatting, where are the files

  * Performance: How well does the model work
    * Biases and scores for specific experiments, in comparison to theoretical solutions, observations, analyses, or other models.
    * Numerical performance for specific experiments and technical setups.

  * User manual: From the code to the experiments
    * Where to find the model code and scripts
    * How to compile the model on the main machines at DKRZ
    * Hot to make experiments

  * Tutorials: Documentation made for training courses
    * Details depend on the goal of the course
    * For getting started on the base of selected experiments
    * Typically includes aspects of formulation, implementation and user manual