This inheritance list is sorted roughly, but not completely, alphabetically:

[detail level 12345]

APIUpgrader	Helper for upgrading source code to use newer APIs
ArrayPool< T >	Lightweight Array Pool
AstarColor	Stores editor colors
AstarData	Stores the navigation graphs for the A* Pathfinding System
AstarMath	Utility functions for working with numbers and strings
AstarProfiler
AstarSerializer	Handles low level serialization and deserialization of graph settings and data
AstarSplines	Contains various spline functions
AstarUpdateChecker	Handles update checking for the A* Pathfinding Project
AstarWorkItem	An item of work that can be executed when graphs are safe to update
Attribute
CustomGraphEditorAttribute	Added to editors of custom graph types
JsonMemberAttribute
JsonOptInAttribute
BBTree.BBTreeBox
BinaryHeap	Binary heap implementation
RecastMeshGatherer.CapsuleCache
Checksum	Calculates checksums of byte arrays
CompactVoxelCell	CompactVoxelCell used for recast graphs
CompactVoxelSpan	CompactVoxelSpan used for recast graphs
Connection	Represents a connection to another node
TileHandler.Cut	Internal class describing a single NavmeshCut
TileHandler.CuttingResult	Internal class representing a mesh which is the result of the CutPoly method
OptimizationHandler.DefineDefinition
Draw	Helper methods for drawing gizmos and debug lines
Editor
AnimationLinkEditor
AstarPathEditor
EditorBase	Helper for creating editors
AILerpEditor
BaseAIEditor
LegacyAIPathEditor
LegacyRichAIEditor
GraphUpdateSceneEditor	Editor for GraphUpdateScene
NavmeshCutEditor
RaycastModifierEditor
RVOControllerEditor
LegacyRVOControllerEditor
RVOSimulatorEditor
SeekerEditor
SmoothModifierEditor
RecastMeshObjEditor
RVONavmeshEditor
RVOSquareObstacleEditor
EditorGUILayoutx	Handles fading effects and also some custom GUI functions such as LayerMaskField
EditorWindow
AstarUpdateWindow
EuclideanEmbedding	Implements heuristic optimizations
Exception
ThreadControlQueue.QueueTerminationException
FadeArea	Editor helper for hiding and showing a group of GUI elements
Funnel	Implements the funnel algorithm as well as various related methods
Funnel.FunnelPortals	Funnel in which the path to the target will be
GraphCollision	Handles collision checking for graphs
GraphEditorBase	Defined here only so non-editor classes can use the target field
GraphEditor
GridGraphEditor
LayerGridGraphEditor
NavMeshGraphEditor
PointGraphEditor
RecastGraphEditor	Editor for the RecastGraph
GraphHitInfo	Returned by graph ray- or linecasts containing info about the hit
GraphMeta	Metadata for all graphs included in serialization
GraphNode	Base class for all nodes
GridNodeBase	Base class for GridNode and LevelGridNode
GridNode	Node used for the GridGraph
LevelGridNode	Describes a single node for the LayerGridGraph
MeshNode
TriangleMeshNode	Node represented by a triangle
PointNode	Node used for the PointGraph
NodeLink3Node
AstarDebugger.GraphPoint
GraphSerializationContext	Holds information passed to custom graph serializers
PathProcessor.GraphUpdateLock	Prevents pathfinding from running while held
GraphUpdateObject	Represents a collection of settings used to update nodes in a specific region of a graph
LayerGridGraphUpdate	GraphUpdateObject with more settings for the LayerGridGraph
GraphUpdateProcessor
GraphUpdateShape	Defines a shape for a Pathfinding.GraphUpdateObject
GraphUpdateUtilities	Contains useful functions for updating graphs
GraphVisualizationUtilities	Contains useful functions for visualizing graphs
GridLookup< T >	Holds a lookup datastructure to quickly find objects inside rectangles
Guid	Simple implementation of a GUID
GUIUtilityx	Simple GUI utility functions
GraphUpdateProcessor.GUOSingle	Holds a single update that needs to be performed on a graph
RetainedGizmos.Hasher	Combines hashes into a single hash value
IAgent	Exposes properties of an Agent class
Agent	Internal agent for the RVO system
IAstarAI	Common interface for all movement scripts in the A* Pathfinding Project
AILerp	Linearly interpolating movement script
AIPath	AI for following paths
MineBotAI	AI controller specifically made for the spider robot
LegacyAIPath	AI for following paths
RichAI	Advanced AI for navmesh based graphs
LocalSpaceRichAI	RichAI for local space (pathfinding on moving graphs)
LegacyRichAI	Advanced AI for navmesh based graphs
IAstarPooledObject
BBTree	Axis Aligned Bounding Box Tree
RichPathPart
RichFunnel
RichSpecial
GraphGizmoHelper
RetainedGizmos.Builder	Helper for drawing gizmos
IComparable< Turn >
AdvancedSmooth.Turn	Represents a turn in a path
IComparer< GraphNode >
PointKDTree.CompareX
PointKDTree.CompareY
PointKDTree.CompareZ
IDisposable
GraphGizmoHelper
IEquatable< Int2 >
Int2	Two Dimensional Integer Coordinate Pair
IEquatable< Int3 >
Int3	Holds a coordinate in integers
IGraphInternals	Exposes internal methods for graphs
NavGraph	Base class for all graphs
GridGraph	Generates a grid of nodes
LayerGridGraph	Grid Graph, supports layered worlds
NavmeshBase	Base class for RecastGraph and NavMeshGraph
NavMeshGraph	Generates graphs based on navmeshes
RecastGraph	Automatically generates navmesh graphs based on world geometry
PointGraph	Basic point graph
IMovementPlane	Transforms to and from world space to a 2D movement plane
GraphTransform	Defines a transformation from graph space to world space
INavmesh
INavmeshHolder	Interface for something that holds a triangle based navmesh
NavmeshBase	Base class for RecastGraph and NavMeshGraph
NavmeshTile
NavmeshBase	Base class for RecastGraph and NavMeshGraph
WorkItemProcessor.IndexedQueue< T >	Similar to Queue<T> but allows random access
IntRect	Integer Rectangle
IPathInternals	Used for hiding internal methods of the Path class
Path	Base class for all path types
ABPath	Basic path, finds the shortest path from A to B
CustomPath
FloodPathTracer	Traces a path created with the Pathfinding.FloodPath
MultiTargetPath	A path which searches from one point to a number of different targets in one search or from a number of different start points to a single target
RandomPath	Finds a path in a random direction from the start node
FleePath	Returns a path heading away from a specified point to avoid
XPath	Extended Path
ConstantPath	Finds all nodes within a specified distance from the start
FloodPath	Floods the area completely for easy computation of any path to a single point
IPathModifier	Base for all path modifiers
MonoModifier	Base class for path modifiers which can be attached to GameObjects
AdvancedSmooth	Smoothing by dividing path into turns and straight segments
AlternativePath	Applies penalty to the paths it processes telling other units to avoid choosing the same path
FunnelModifier	Simplifies paths on navmesh graphs using the funnel algorithm
RadiusModifier	Radius path modifier for offsetting paths
RaycastModifier	Simplifies a path using raycasting
SimpleSmoothModifier	Modifier which smooths the path
PathModifier	Base class for path modifiers which are not attached to GameObjects
StartEndModifier	Adjusts start and end points of a path
IRaycastableGraph	Graph which supports the Linecast method
GridGraph	Generates a grid of nodes
NavmeshBase	Base class for RecastGraph and NavMeshGraph
ISerializationCallbackReceiver
VersionedMonoBehaviour	Base class for all components in the package
AstarPath	Core component for the A* Pathfinding System
AIBase	Base class for AIPath and RichAI
AIPath	AI for following paths
RichAI	Advanced AI for navmesh based graphs
AILerp	Linearly interpolating movement script
AstarDebugger	Debugger for the A* Pathfinding Project
BlockManager	Manager for blocker scripts such as SingleNodeBlocker
AnimationLinkTraverser	Example of how to handle off-mesh link traversal
MecanimBridge	Example of how to use Mecanim with the included movement scripts
TurnBasedAI	Helper script in the example scene 'Turn Based'
GraphModifier	GraphModifier is used for modifying graphs or processing graph data based on events
DynamicGridObstacle	Attach this script to any obstacle with a collider to enable dynamic updates of the graphs around it
GraphUpdateScene	Helper class for easily updating graphs
NodeLink	Connects two nodes with a direct connection
NodeLink2	Connects two nodes via two intermediate point nodes
AnimationLink
NodeLink3	Connects two TriangleMeshNodes (recast/navmesh graphs) as if they had shared an edge
RVONavmesh	Adds a navmesh as RVO obstacles
LocalSpaceGraph	Helper for Pathfinding.Examples.LocalSpaceRichAI
MonoModifier	Base class for path modifiers which can be attached to GameObjects
NavmeshClipper	Base class for the NavmeshCut and NavmeshAdd components
NavmeshAdd	Adds new geometry to a recast graph
NavmeshCut	Navmesh cutting is used for fast recast graph updates
ProceduralGridMover	Moves a grid graph to follow a target
RecastMeshObj	Explicit mesh object for recast graphs
RelevantGraphSurface	Pruning of recast navmesh regions
RVOController	RVO Character Controller
LegacyRVOController	RVO Character Controller
RVOObstacle	Base class for simple RVO colliders
RVOSquareObstacle	Square Obstacle for RVO Simulation
RVOSimulator	Unity front end for an RVO simulator
Seeker	Handles path calls for a single unit
SingleNodeBlocker	Blocks single nodes in a graph
TileHandlerHelper	Helper for navmesh cut objects
GridLookup< T >.Item
ITransform	Generic 3D coordinate transformation
GraphTransform	Defines a transformation from graph space to world space
ITransformedGraph	Graph which has a well defined transformation from graph space to world space
GridGraph	Generates a grid of nodes
INavmeshHolder	Interface for something that holds a triangle based navmesh
NavmeshBase	Base class for RecastGraph and NavMeshGraph
ITraversalProvider	Provides additional traversal information to a path request
BlockManager.TraversalProvider	Blocks nodes according to a BlockManager
IUpdatableGraph	Graphs which can be updated during runtime
GridGraph	Generates a grid of nodes
LayerGridGraph	Grid Graph, supports layered worlds
NavMeshGraph	Generates graphs based on navmeshes
PointGraph	Basic point graph
RecastGraph	Automatically generates navmesh graphs based on world geometry
IVersionedMonoBehaviourInternal	Exposes internal methods from Pathfinding.VersionedMonoBehaviour
VersionedMonoBehaviour	Base class for all components in the package
IWorkItemContext	Interface to expose a subset of the WorkItemProcessor functionality
WorkItemProcessor
LegacyEditorHelper
Line	ORCA Line
AnimationLink.LinkClip
LinkedLevelNode	Internal class used by the LayerGridGraph
LinkedVoxelSpan
ListExtensions	Extension methods for List<T>
ListPool< T >	Lightweight List Pool
LockFreeStack	Implements a lock free multiple producer - single consumer stack for the Path object
Memory	Various utilities for handling arrays and memory
ObjImporter.meshStruct
RetainedGizmos.MeshWithHash
MonoBehaviour
AIDestinationSetter	Sets the destination of an AI to the position of a specified object
DebugUtility	Helper for drawing debug information for the recast graph
Astar3DButton	Helper script in the example scene 'Turn Based'
AstarSmoothFollow2	Smooth Camera Following
BezierMover	Moves an object along a spline
DoorController	Example script used in the example scenes
ExampleMover
GroupController	RVO Example Scene Unit Controller
HexagonTrigger	Helper script in the example scene 'Turn Based'
LightweightRVO	Lightweight RVO Circle Example
ManualRVOAgent	Player controlled character which RVO agents will avoid
ObjectPlacer	Small sample script for placing obstacles
PathTypesDemo	Demos different path types
ProceduralWorld	Example script for generating an infinite procedural world
RVOAgentPlacer	Places ROV agents in circles
RVOExampleAgent	Example movement script for using RVO
TurnBasedDoor	Helper script in the example scene 'Turn Based'
TurnBasedManager	Helper script in the example scene 'Turn Based'
NavmeshClamp	Attach to any GameObject and the object will be clamped to the navmesh
Patrol	Simple patrol behavior
RecastTileUpdate	Updates the recast tile(s) it is in at start, needs RecastTileUpdateHandler
RecastTileUpdateHandler	Helper for easier fast updates to recast graphs
TargetMover	Moves the target in example scenes
UnityReferenceHelper	Helper class to keep track of references to GameObjects
VersionedMonoBehaviour	Base class for all components in the package
MovementUtilities
NNConstraint	Nearest node constraint
FloodPathConstraint	Restrict suitable nodes by if they have been searched by a FloodPath
PathNNConstraint	A special NNConstraint which can use different logic for the start node and end node in a path
NNInfo	Result of a nearest node query
NNInfoInternal	Internal result of a nearest node query
RVOQuadtree.Node	Node in a quadtree for storing RVO agents
PointKDTree.Node
ObjectPool< T >	Lightweight object Pool for IAstarPooledObject
ObjectPoolSimple< T >	Lightweight object Pool
ObjImporter
ObstacleVertex	One vertex in an obstacle
OptimizationHandler	Helper for enabling or disabling compiler directives
ParallelWorkQueue< T >	Helper for parallelizing tasks
PathEndingCondition	Customized ending condition for a path
ABPathEndingCondition	Ending condition which emulates the default one for the ABPath
EndingConditionProximity	Ending condition which stops a fixed distance from the target point
EndingConditionDistance	Target is found when the path is longer than a specified value
PathHandler	Handles thread specific path data
PathInterpolator	Interpolates along a sequence of points
PathNode	Stores temporary node data for a single pathfinding request
Funnel.PathPart	Part of a path
PathPool	Pools path objects to reduce load on the garbage collector
PathPool< T >	Pools path objects to reduce load on the garbage collector
PathProcessor
PathReturnQueue
AstarDebugger.PathTypeDebug
PathUtilities	Contains useful functions for working with paths and nodes
PointKDTree	Represents a collection of GraphNodes
Polygon	Utility functions for working with polygons, lines, and other vector math
ProceduralWorld.ProceduralPrefab
ProceduralWorld.ProceduralTile
Profile
AstarProfiler.ProfilePoint
Progress	Progress info for e.g a progressbar
PropertyAttribute
EnumFlagAttribute
PropertyDrawer
EnumFlagDrawer
RVOQuadtree.QuadtreeQuery
RasterizationMesh	Represents a mesh which will be rasterized
ExtraMesh	Represents a mesh
RecastBBTree	Axis Aligned Bounding Box Tree
RecastBBTreeBox
RecastMeshGatherer
RetainedGizmos	Helper for drawing Gizmos in a performant way
RichPath
GridLookup< T >.Root
RVOQuadtree	Quadtree for quick nearest neighbour search of rvo agents
SerializeSettings	Holds settings for how graphs should be serialized
Simulator	Local Avoidance Simulator
StackPool< T >	Lightweight Stack Pool
GridGraph.TextureData	Used for using a texture as a source for a grid graph
ThreadControlQueue	Queue of paths to be processed by the system
TileHandler	Utility class for updating tiles of navmesh/recast graphs
TileHandler.TileType	A template for a single tile in a navmesh/recast graph
TinyJsonDeserializer	A very tiny json deserializer
TinyJsonSerializer	A very tiny json serializer
BinaryHeap.Tuple	Item in the heap
AdvancedSmooth.TurnConstructor	Abstract turn constructor
AdvancedSmooth.ConstantTurn	Constant turning speed
AdvancedSmooth.MaxTurn	Type of turn
APIUpgrader.UpgradeItem
Utility	Various utilities for voxel rasterization
VectorMath	Various vector math utility functions
Agent.VO	Velocity Obstacle
Agent.VOBuffer	Very simple list
VoxelArea	Stores a voxel field
VoxelCell	VoxelCell used for recast graphs
VoxelContour	VoxelContour used for recast graphs
VoxelContourSet	VoxelContourSet used for recast graphs
Voxelize	Voxelizer for recast graphs
VoxelMesh	VoxelMesh used for recast graphs
VoxelPolygonClipper	Utility for clipping polygons
VoxelSpan	VoxelSpan used for recast graphs
WindowsStoreCompatibility
Simulator.Worker
Simulator.WorkerContext