Clicking on any object while in Describe mode will display the Property Sheet for the object listing such things as its position, size, color and layer as appropriate for each type of object. Certain values can be changed to modify the object. If a track is connected to other tracks, then some values (ie. End Point positions) can not be changed.
The object is highlighted by a grey area.
Most commands return to Describe mode then they terminate unless the command is sticky.
Note: the Default Command radio button on the Command Options dialog controls whether the Describe or the Select command is used as the default command.