There are two basic ways to view your scene in Maya:
This shows which nodes are parents and children of other nodes. You can use the Outliner to view and edit the scene in this type of view.
The Outliner shows a hierarchical list of all objects in the scene.
This shows which nodes provide input or output to other nodes. You can use the Hypergraph or Node Editor to view and edit the scene in this type of view.
The Hypergraph shows a network of boxes representing nodes, and the lines that connect them to represent their relationships.