Final answer:
Transverse waves have matter moving at right angles to the direction of travel, such as on musical strings and in electromagnetic waves. Longitudinal waves oscillate parallel to the direction, like sound waves in fluids.
Step-by-step explanation:
Waves that have the matter moving back and forth at right angles to the direction that the wave travels are known as transverse waves. In these types of waves, the disturbance in the medium is perpendicular to the direction of propagation. For instance, the waves on the strings of musical instruments are transverse waves, and so are electromagnetic waves, like visible light. On the other hand, in longitudinal waves, the medium oscillates parallel to the wave's direction of propagation, as seen with sound waves in air and water, which are periodic variations in pressure transmitted in fluids.