3D cylindrical coordinates specify a location by a distance from the UCS origin in the XY plane, an angle from the X axis in the XY plane, and a Z value.
For cylindrical coordinate entry, you specify a point using the following syntax:
X < angle , Z
In the illustration below, dynamic input is turned off, so 5<30,8 specifies a point 5 units from the UCS origin in the XY plane, 30 degrees from the positiveX axis in the XY plane, and 8 units along the positive Z axis.
You can enter absolute coordinates, which are based on the UCS origin, or you can enter relative coordinates, which are based on the last point entered.