Though black holes themselves may not radiate energy, electromagnetic radiation and matter particles may be radiated from just outside the event horizon via Hawking radiation.

Based on this principle, Hawking set out to show that black holes do not radiate.

However, this concept demonstrates that black holes can radiate energy, which conserves entropy and solves the incompatibility problems with the second law of thermodynamics.

Stephen Hawking theorized that black holes radiate thermally with no regard to how they are formed.

If a black hole could not radiate, it could have no temperature and thus no entropy.

Small black holes therefore have higher temperatures and radiate their energy more rapidly than larger black holes.

The law implied that black holes were hot, a contradiction of classical physics that said black holes could not radiate heat.

In this process, these small black holes radiate away matter.

The black holes created in this way would then accrete and radiate, driving a wind which acts back on the accretion flow.

This is his understanding that black holes radiate and are not really black.