Here is a list of all modules with brief descriptions:

Madiabatic_density_mod	Module for prepare_density routine (not sure what it is supposed to do or if it is even used...) Contains its own particle initialization, 1D deposition and solver routines
Mantenna_mod	Module for applying external charge and current density perturbations, or electrostatic and magnetic potentials
Mbackground	Different background distribution functions and their gradients
Mboundaryconditions	Solver Adaptor pattern
Mbsplinesclass
Mcollisions_mod
Mcomisland
Mcontrol_all
Mderived_inputs	Define derived types "input_[...]" to attach descriptions and default values to input variables Most of the commonly used operators are overloaded to operate on derived input values (e.g. myinput==0 <=> myinputval==0)
Mdiagnostic_bspline
Mdiagnostics_mod
Mefluid	Electron fluid model (FLU-ORB)
Mepilogue
Mequil_mod
Mexamples
Mfft_interface	Module for performing FFT
Mfftw3
Mfields_mod
Mfourierfilter
Mglobals
Mglobals_diag
Mgyrodensity_correct
Mgyropoints
Minterfacesolverinorb5
Minterpos_module
Mislands_mod
Mlarmor
Mloadtor
Mmathutil	Math functions
Mmatrix_coeff
Mmoments
Monestep
Mparmove_mod	Routines for moving markers across parallel subdomains
Mpart_fields	Particle-to-fields and fields-to-particle operations
Mpdespline	Module containing B-spline utilities for solvers
Mpputil
Mprecision_kinds
Mprofile_update_mod
Mprofiler	Simple interface to Score-P for profiling ORB5
Mprofileswrapper
Mpszs_mod
Mquadtree_mod
Mrandom_coll
Mrandom_generator
Mreadinput	Module for reading the input file and filling data in globals.F90
Msolver_data
Msolver_mod
Msorting_mod	Module containing sorting routines
Msources
Mtestfunctions
Mutil
Mutil_orb
Mvis3d	Output 3D arrays for 3D visialization