29.2The four basic types of motion

Between two voices:

Contrary motion

one rises, the other falls.

Example:

RH: E → F

LH: C → B

Similar motion

both move same direction, different intervals.

RH: E → G

LH: C → D

Parallel motion

both move same direction by same interval.

Example in thirds:

E-G → F-A → G-B

Oblique motion

one voice stays, the other moves.

RH: G → G → G

LH: C → B → A

All four are useful.