Here is a list of all modules:
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 Helper macros for running commands through Python interpreter
 Helper functions for running commands through Python interpreter
 CoreThese are the core components of FreeCAD
 BaseBasic structures used by other FreeCAD components
 Geometry primersBasic structures used by geometric objects
 Memory debuggingMemory debugging tools
 Units systemThe quantities and units system enables FreeCAD to work transparently with many different units
 AppThe part of FreeCAD that works without GUI (console or server mode)
 DocumentThe Base class of the FreeCAD Document
 Document ObjectBase class of all objects handled in the Document
 Expressions frameworkThe expression system allows users to write expressions and formulas that produce values
 Property frameworkSystem to access object properties
 GuiThe 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
 WorkbenchesMost of FreeCAD's functionality is defined in dedicated Workbenches
 CloudMulti paragraph description goes here
 C++ workbenchesThese workbenches are programmed primarily in C++, but most provide a Python API as well
 DrawingManages output of 2D sheets from FreeCAD documents
 ImageTools and utilities to work with bitmap images
 CloudMulti paragraph description goes here
 MeshTools to work with polygon meshes
 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
 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
 SpreadsheetTools to work with spreadsheets
 StartThe start page of FreeCAD
 TechDrawFramework to produce 2D drawing from FreeCAD documents
 TestTest framework of FreeCAD
 WebThe webkit-based web browser of FreeCAD
 Python workbenchesThose are workbenches programmed primarily in Python
 Addon ManagerApplication that handles the installation of user-made workbenches and macros
 ArchArchitecture and BIM tools
 DraftBasic 2D drawing tools and other generic tools
 draftfunctionsModules with functions for use with scripted objects and GuiCommands
 draftgeoutilsFunctions that are meant to handle different geometrical operations
 draftguitoolsModules that define the workbench GuiCommands to perform actions
 draftmakeModules with functions to create the custom scripted objects
 draftobjectsModules that contain classes that define custom scripted objects
 drafttaskpanelsModules with classes that handle task panels of the GuiCommands
 drafttestsModules that define classes used for unit testing the workbench
 draftutilsUtility modules that are used throughout the workbench
 draftviewprovidersClasses that define viewproviders for the scripted objects
 FemFinite Elements Analysis workbench
 OpenSCADInterface with OpenSCAD
 PathTools to generate CNC toolpaths and G-Code
 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
 PlotUtilities and tools to draw curves diagrams
 Utility modulesModules that provide utility tools to FreeCAD but don't define a workbench
 OfflineRenderingUtilsUtility functions to work with FreeCAD files in console mode
 DraftGeomUtilsShape manipulation utilities for the Draft workbench
 DraftVecUtilsVector math utilities used in Draft 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
 PyCXXC++ facilities to make it easier to write Python extensions
 Zipios++C++ library for reading and writing Zip file
 Salome SMESHThe Salome SMESH module is used in Fem and Mesh workbenches
 Dice 3DSThe Dice 3DS library provides 3DStudio files import to the Arch module
 WildMagic4Excerpts from version 4.0.0 of Wild Magic Library which were integrated to FreeCAD's Mesh module