Hypershade Edit menu

Delete
Deletes the selected node(s). When you delete a node from Hypershade, it's deleted from the session.
Delete Unused Nodes
Deletes nodes not assigned to geometry or particles.
Delete Duplicate Shading Networks
Deletes redundant shading networks.
Delete All by Type
Deletes all nodes of the type you select, whether they are assigned or not.
Revert Selected Swatches
Reverts the selected swatches to their default shapes.
Select All by Type
Highlights all the node swatches you select from this menu.
Select Objects with Materials
Highlights all the node swatches from objects that have materials assigned to them.
Select Materials from Objects
Highlights all the node swatches from selected objects. For example, if you want to know which materials are used by objects A,B,C, you can first select objects A,B,C, then select this menu item to select materials related to A,B,C. Objects A,B,C will no longer be selected. The initial objects you selected can be a normal object or a group or faces of a polygon geometry.
Duplicate

Duplicates the selected node or shading network. To duplicate a node without its network, select the node and select Edit > Duplicate > Without Network. To duplicate a node and connect it to the same network (in effect, sharing the network), select Edit > Duplicate > With Connections to Network.

See About shading networks.

Edit Texture
Opens your default image editor and allows you to edit the texture.