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+@mainpage
+
+# An introduction to the DAWN software
+
+The DAWN software provides an XML-based interface to the BioCro C++
+library for running simulations of plant growth.  It consists of two main components:
+
+* The DAWN application ("`dawn`") is a command-line program taking the
+  name of an XML file specifying a simulation specification as a
+  parameter.  When run, it produces an XML document showing the
+  results of that simulation.
+
+* The DAWN library ("`libdawn_lib.dylib`" or "`libdawn_lib.a`") is a
+  library that provides a function for running such a simulation.  A
+  program using the library may then extend this functionality in any
+  way it chooses.  The library also provides classes that define
+  object types for working with the inputs and output of this
+  function.
+
+## The `dawn` command-line application
+
+The `dawn` command in its most basic form takes the name of an XML
+file containing a simulation specification as its argument and returns
+an XML document presenting the result of running that simulation.
+Options exist for skipping schema validation of the input, for
+specifying drivers in a separate file, and for wrting the result to a
+file rather than standard output, among other things.  This is
+explained in more detail in the README file for this repository and in
+the command-line help given by running `dawn --help`.
+
+## Using the DAWN library
+
+Application programs may use the DAWN library to run simulations as part of their processing.
+