A cube will appear at the origin. Before creating the cube it was grayed out, or desensitized. The sensitive Edit button indicates that there is something ready to be edited. Not surprisingly, it's the cube that was just created. All new objects in the scene window are placed on the edit menu at the time of creation.
Many people ask why there is an edit menu at all.
The reason is that there can be many objects on the queue to be edited at any one time, but only one object can actually be edited at a time. A large dialog window will pop up. The cube should also have changed. Take a look at the cube. There are several things to take notice of.