* Shortwave radiation is the type of energy emitted by the Sun. It's high energy, and includes visible light, ultraviolet radiation, and some infrared radiation.

* Longwave radiation is the type of energy emitted by the Earth. It's lower energy, and falls mostly within the infrared portion of the electromagnetic spectrum.

Think of it like this:

* The Sun is a hot object, emitting a lot of high-energy radiation.

* The Earth is a cooler object, emitting lower-energy radiation.

Key takeaway: The Earth absorbs shortwave radiation from the Sun and re-emits it as longwave radiation. This process is a fundamental part of the Earth's energy balance and climate system.