# Node > The base class for all user-accessible nodes in a graph. ## Definition * **Type:** Class * **Namespace:** [Unity.GraphToolkit.Editor](/engine/6000.6/script-reference/unity/graphtoolkit/editor.md) * **Assembly:** UnityEditor * **Implements:** [INode](/engine/6000.6/script-reference/unity/graphtoolkit/editor/inode.md) ```csharp public abstract class Node : INode ``` ## Remarks Inherit from this class to define custom node types that appear in the graph. The [Node](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node.md) class provides lifecycle hooks, serialization support, and the structure needed to define ports, UI behaviors, and custom logic. This class forms the foundation of all user-defined nodes in a graph-based tool, including variable nodes, context nodes, and subgraph nodes. To create a custom node, derive from [Node](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node.md), define its input and output ports using a port builder in [Node.OnDefinePorts](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/ondefineports.md), and define its [INodeOption](/engine/6000.6/script-reference/unity/graphtoolkit/editor/inodeoption.md)s in [Node.OnDefineOptions](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/ondefineoptions.md). This class is used in combination with other types like [INode](/engine/6000.6/script-reference/unity/graphtoolkit/editor/inode.md), [IPort](/engine/6000.6/script-reference/unity/graphtoolkit/editor/iport.md), and [Node.Graph](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/graph.md) to construct and manage node-based workflows. Additional Resources: [INode](/engine/6000.6/script-reference/unity/graphtoolkit/editor/inode.md), [ContextNode](/engine/6000.6/script-reference/unity/graphtoolkit/editor/contextnode.md), [BlockNode](/engine/6000.6/script-reference/unity/graphtoolkit/editor/blocknode.md), [IVariableNode](/engine/6000.6/script-reference/unity/graphtoolkit/editor/ivariablenode.md), [ISubgraphNode](/engine/6000.6/script-reference/unity/graphtoolkit/editor/isubgraphnode.md) ## Properties | Property | Description | | ---------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------- | | [DefaultColor](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/defaultcolor.md) | The highlight color of the node. The highlight is located on the upper border of nodes, and on the upper and lower borders of context nodes. | | [FillAmount](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/fillamount.md) | The progress fill amount displayed on the node's accent bar, expressed as a percentage. | | [Graph](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/graph.md) | The [Node.Graph](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/graph.md) that contains this node. | | [ID](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/id.md) | The globally unique identifier for this node. | | [InputPortCount](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/inputportcount.md) | The number of input ports on the node. | | [NodeOptionCount](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/nodeoptioncount.md) | The number of node options defined in the node. | | [NodeOptions](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/nodeoptions.md) | The node options defined on this node. | | [OutputPortCount](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/outputportcount.md) | The number of output ports on the node. | | [Position](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/position.md) | The position of the node in the graph. | | [Subtitle](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/subtitle.md) | The secondary text displayed in the node's header. | | [Title](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/title.md) | The main text displayed in the node's header. | | [Tooltip](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/tooltip.md) | The text displayed when hovering over the node's header. | ## Methods | Method | Description | | ------------------------------------------------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [DefineNode](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/definenode.md) | Defines the structure of the node by building its ports and options. | | [GetInputPort](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/getinputport.md) | Retrieves an input port using its index. | | [GetInputPortByName](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/getinputportbyname.md) | Retrieves an input port using its name. | | [GetInputPorts](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/getinputports.md) | Retrieves all input ports on the node in the order they are displayed. | | [GetNodeOption](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/getnodeoption.md) | Retrieves a node option using its zero-based index. | | [GetNodeOptionByName](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/getnodeoptionbyname.md) | Retrieves a node option using its name. | | [GetOutputPort](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/getoutputport.md) | Retrieves an output port using its index in the displayed order. | | [GetOutputPortByName](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/getoutputportbyname.md) | Retrieves an output port using its name. | | [GetOutputPorts](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/getoutputports.md) | Retrieves all output ports on the node in the order they are displayed. | | [OnDefineOptions](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/ondefineoptions.md) | Called during [Node.DefineNode](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/definenode.md) to define the options available on the node. | | [OnDefinePorts](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/ondefineports.md) | Called during [Node.DefineNode](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/definenode.md) to define the input and output ports of the node. | | [OnDisable](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/ondisable.md) | Called when the node is removed or when the graph is disabled. | | [OnEnable](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/onenable.md) | Called when the node is created or when the graph is enabled. | | [RemoveFromGraph](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/removefromgraph.md) | Removes the node from its graph. | ## Interfaces | Interface | Description | | --------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [Node.IOptionDefinitionContext](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/ioptiondefinitioncontext.md) | Interface that provides methods to declare node options inside a node. | | [Node.IPortDefinitionContext](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/iportdefinitioncontext.md) | Interface that provides methods to define input and output ports during [Node.OnDefinePorts](/engine/6000.6/script-reference/unity/graphtoolkit/editor/node/ondefineports.md) execution. |