When an object has any temperature above 0K, that means the chemically bonded particles are moving around/vibrating. This movement of charged particles (release of internal energy) creates electromagnetic radiation (photons).
The other radiation you are talking about is also energy being released as photons, but it is from electrons in an excited state falling to a lower energy state.
Molecules can take in energy differently. Some frequencies of incoming energy produce bond movement/vibrations, and other frequencies can excite an electron's state. Consequently, when the energy is released, it can be in different frequencies (infrared/heat, visible light, UV, etc.) depending on the amount of energy lost. Since electron orbitals are discrete states, the release of energy from an electron going to a lower orbital is a discrete frequency of light.
And all those virtual photons that make the electron hang around near the the nucleus.
It seems like its photons all the way down...