A mechanical wave is a type of wave that requires a medium to travel through. In other words, it needs some kind of substance, such as air, water, or a solid material, to move through.
One example of a mechanical wave is a sound wave. When you speak or make a noise, you create sound waves that travel through the air. The sound waves cause the air particles to vibrate, which in turn causes the sound to be heard by someone nearby.
Another example is a water wave. When you throw a stone into a pond, it creates ripples that travel outward through the water. The ripples are a type of mechanical wave, because they need the water to move through.
Overall, mechanical waves are important because they allow energy to be transferred from one place to another, even over long distances!