A wave is a disturbance that carries energy from one place to another.

Types of waves

1. Mechanical Waves - e.g., water waves, sound waves, and waves on strings. The wave requires a medium through which to travel, but there is no net flow of mass though the medium, only a flow of energy. We'll do these this week.
2. Electromagnetic Waves - e.g., light, x-rays, microwaves, radio waves, etc. They're just different frequency ranges of the same kind of wave, and they don't need a medium. We'll look at these after Spring Break.
3. Matter Waves - waves associated with things like electrons, protons, and other tiny particles. We'll do these toward the end of this course.