Wave propagation refers to the movement of waves through a medium, such as air, water, or solid materials. Waves can be mechanical, like sound waves, which require a medium to travel, or electromagnetic, like light waves, which can move through a vacuum. The speed and behavior of wave propagation depend on the properties of the medium and the type of wave. As waves travel, they can reflect, refract, or diffract, altering their direction and intensity. For example, when a sound wave encounters a barrier, it may bounce back (reflection) or change direction as it passes through a different medium (refraction). Understanding wave propagation is essential in fields like acoustics, optics, and seismology.