Microwaves are a type of electromagnetic energy like light waves. The one difference is that microwaves cannot be seen by the human eye. Microwaves have longer wavelengths than light waves. Like light waves, microwaves may be reflected and concentrated. Microwaves pass easily through rain, smoke, and fog which block lightwaves. Microwaves can pass through the ionosphere (which surrounds the earth and blocks or reflects longer radio waves).Microwaves are used in aircraft.