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For a long time, it was believed that Hawking radiation is thermal and doesn't carry information, except for the mass/radius/temperature of the black hole.

In 2004, Hawking conceded that, due to the holographic principle, information wasn't lost. The basic idea is that the infalling matter can gravitationally deform the horizon and thus modify the distribution of Hawking radiation from the pure thermal emission. And the interesting point is that the entropy of the black hole is proportional to its area and not its volume (holography), so the deformation of the horizon is sufficient to recover all the "missing" information.