CopySubdir is a module that, as the name suggests, copies one SUBDIR to another. The command
CopySubdir PRE=/pre DATA=data RUN=run/work SUBDIR=subdir OUTDIR=outdir
is equivalent to typing
cp -r /pre/data/run/work/subdir /pre/data/run/work/outdir
at a UNIX command line. The module may look unnecessary in comparison to cp, but it is arguably easier to use in the context of a script module, when the command-line arguments are already defined.