TreeMap: Update Node topic (DevExpress#8031) (DevExpress#8036)

Author: arman-boyakhchyan

api-reference/10 UI Components/dxTreeMap/6 Node/Node.md

@@ -5,7 +5,14 @@ export: dxTreeMapNode
 ---
 ---
 ##### shortDescription
-This section describes the **Node** object, which represents a treemap node.
+This section describes the **node** object.
 
 ---
-**Node** objects are accessible within certain event handlers, for example, [onNodesInitialized](/api-reference/10%20UI%20Components/dxTreeMap/1%20Configuration/onNodesInitialized.md '/Documentation/ApiReference/UI_Components/dxTreeMap/Configuration/#onNodesInitialized'), [onNodesRendering](/api-reference/10%20UI%20Components/dxTreeMap/1%20Configuration/onNodesRendering.md '/Documentation/ApiReference/UI_Components/dxTreeMap/Configuration/#onNodesRendering'), etc. Also, you can obtain these objects using the [getRootNode()](/api-reference/10%20UI%20Components/dxTreeMap/3%20Methods/getRootNode().md '/Documentation/ApiReference/UI_Components/dxTreeMap/Methods/#getRootNode') and [getCurrentNode()](/api-reference/10%20UI%20Components/dxTreeMap/3%20Methods/getCurrentNode().md '/Documentation/ApiReference/UI_Components/dxTreeMap/Methods/#getCurrentNode') methods.
+The following image illustrates TreeMap node types:
+
+<img src="/images/TreeMap/treemap-node.png" alt="TreeMap node types" style="width: 1100px;"/>
+
+1. [Group Node](/Documentation/ApiReference/UI_Components/dxTreeMap/Configuration/group/)
+2. [Child Node](/Documentation/ApiReference/UI_Components/dxTreeMap/Configuration/#childrenField)
+
+You can access the root TreeMap **node** object within event handlers such as [onNodesInitialized](/api-reference/10%20UI%20Components/dxTreeMap/1%20Configuration/onNodesInitialized.md '/Documentation/ApiReference/UI_Components/dxTreeMap/Configuration/#onNodesInitialized') and [onNodesRendering](/api-reference/10%20UI%20Components/dxTreeMap/1%20Configuration/onNodesRendering.md '/Documentation/ApiReference/UI_Components/dxTreeMap/Configuration/#onNodesRendering'), as well as through the [getRootNode()](/api-reference/10%20UI%20Components/dxTreeMap/3%20Methods/getRootNode().md '/Documentation/ApiReference/UI_Components/dxTreeMap/Methods/#getRootNode') method. To get all **node** instances within a component, call the [getAllNodes()](/Documentation/ApiReference/UI_Components/dxTreeMap/Node/Methods/#getAllNodes) method on the root **node**.