Question

What is blackbody radiation?

Answer 1

1. Even though in thermal equilibrium, an ideal black body seems to be essentially an enclosed cavity-like structure that receives all input radiation as well as re-emits radiation that would be typical of the systems, regardless of the source of incident radiation, the emitted energy is referred to as black body radiation.
2. A black body should indeed produce radiation at almost the similar rate that it consumes, hence it should also be a competent emitter of energy, generating electromagnetic waves throughout all frequencies.