Here is a list of all modules:
[detail level 1234]
 Parameters helper macrosCollections of macros for managing groups of parameters
 Field accessorsTo abstract parameter field details
 Field stringizers
 Looper macrosMacros for looping through sequence to parameters
 Common helpers
 Enum convert helpers
 Python helperHelper macros for Python bindings
 Python doc helperGenerate argument doc string for Python
 Property MacrosHelper macros for FreeCAD properties
 CoreThis is the core functionality of FreeCAD
 BaseBasic structures used by other FreeCAD components
 Memory debuggingMemory debugging tools
 App sideThe part of FreeCAD that works without GUI (console or server mode)
 Property frameworkSystem to access object properties
 Gui sideThe Graphical User Interface of FreeCAD and the 3D View
 Command FrameworkStructure for registering commands to the FreeCAD system
 Internationalization with FreeCADThe internationalization of FreeCAD makes heavy use of the internationalization support of Qt
 3D ViewerThe 3D Viewer is one of the major components in a CAD/CAE systems
 Workbench FrameworkFreeCAD provides the possibility to have one or more workbenches for a module
 Global application levelThe Main classes define general application settings
 WorkbenchesAdditional functionality and GUI tools
 Python workbenchesThose are workbenches programmed fully in Python
 ArchArchitecture and BIM tools
 DraftBasic 2D drawing tools and other generic tools
 DraftGeomUtilsShape manipulation utilities for the Draft workbench
 DraftVecUtilsVector math utilities used in Draft workbench
 OpenSCADInterface with OpenSCAD
 PlotUtilities and tools to draw curves diagrams
 ShipTools towork with ship hulls
 C++ workbenchesThose are workbenches programmed primarily in C++
 DrawingManages output of 2D sheets from FreeCAD documents
 FemFinite Elements Analysis workbench
 ImageTools and utilities to work with bitmap images
 MeshTools to work with polygon meshes
 WildMagic4Excerpts from version 4.0.0 of Wild Magic Library which were integrated to FreeCAD's Mesh module
 MeshPartPart to Mesh (and vice-versa) conversion tools
 PartMain anchor point with OpenCasCade functionality, base geometry tools
 PartDesignComplete suite of tools to design Parts based on Sketches
 PathTools to generate CNC toolpaths and G-Code
 PointsTools to work with point clouds
 RaytracingProvides tools to generate rendered images using external renderers
 ReverseEngineeringGenerate Part shapes from Mesh and Points based objects
 RobotSimulates 6-axis robot movements
 SketcherConstrained 2D objects
 StartThe start page of FreeCAD
 TechDrawFramework to produce 2D drawing from FreeCAD documents
 TestTest framework of FreeCAD
 WebThe webkit-based web browser of FreeCAD
 Utility modulesModules that provide utility tools to FreeCAD but don't define a workbench
 ImportBrief Utilities to import various file formats using OpenCasCade OCAF
 MaterialMaterials support for FreeCAD
 Embedded 3rd party librariesImportant tools and libraries incorporated to FreeCAD