Shock waves can be:
- Normal: at 90° (perpendicular) to the shock medium's flow direction.
- Oblique: at an angle to the direction of flow.
- Bow: Occurs upstream of the front (bow) of a blunt object when the upstream velocity exceeds Mach 1.
Some other terms
- Shock Front: an alternative name for the shock wave itself
- Contact Front: in a shock wave caused by a driver gas (for example the "impact" of a high explosive on the surrounding air), the boundary between the driver (explosive products) and the driven (air) gases. The Contact Front trails the Shock Front.
Read more about this topic: Shock Wave