Here's why:

* Mechanical waves are disturbances that travel through a material medium, transferring energy but not matter. They need the particles of the medium to vibrate and transmit the wave.

* Examples of mechanical waves:

* Sound waves: Travel through air, water, or solids.

* Water waves: Travel through water.

* Seismic waves: Travel through the Earth's crust.

In contrast, electromagnetic waves, like light, do not require a medium to travel. They can travel through the vacuum of space.