1. Drag empty space to pan.
2. Use mouse wheel to scroll vertically.
3. Hold "Ctrl" and use mouse wheel to zoom.
4. Click a node to select it.
5. Double click a node to edit it's text.
6. Drag & drop a node to change it's position
7. "Enter" to add a sibling node of the selected node.
8. "Ctrl + Enter" to add a child node of the selected node.
9. "Ctrl + C" to copy the selected node.
10. "Ctrl + X" to cut the selected node.
11. "Ctrl + V" to paste copied node to the selected node.