Space Handles

In 3D sketching, a graphical space handle helps maintain your orientation while you sketch on several planes. The space handle appears when the first point of a sketch entity is defined on a selected plane. Using the space handle, you can select the axis along which you want to sketch.

When sketching on a 3D plane, no graphical assistant is displayed since you are creating a 3D sketch in 2D space.
By default, you sketch relative to the default coordinate system in the model. To switch to one of the other two default planes, click the sketch tool and press Tab. The origin of the current sketch plane is displayed.