The event horizon is the boundary in spacetime beyond which the gravitational pull becomes so strong that nothing, not even light, can escape.

The singularity is the point of infinite density and gravity at the center of a black hole, where the laws of physics as we know them break down.

The accretion disk is the disk of gas and dust that orbits a black hole, and is heated to extremely high temperatures by friction.

A wormhole is a theoretical tunnel connecting two different regions of spacetime, allowing for faster-than-light travel.

Accretion is the process by which matter falls onto a black hole, releasing energy and increasing its mass.

Spaghettification is the phenomenon where matter is stretched and compressed as it approaches a black hole, due to the extreme gravitational forces.

Hawking radiation is the theoretical radiation emitted by black holes due to quantum effects, leading to their eventual evaporation.

The Oppenheimer-Volkoff limit is the theoretical limit on the mass of a black hole, beyond which it would collapse under its own gravity.

The Schwarzschild radius is the radius of a black hole's event horizon, beyond which nothing can escape.

A binary black hole is a system where two black holes orbit around each other, often emitting gravitational waves.

Supermassive black holes are the largest type of black hole found in the universe, with masses millions or billions of times that of the Sun.

A quasar is an active galactic nucleus powered by a supermassive black hole, emitting enormous amounts of energy.

A blazar is a type of quasar that emits a powerful jet of particles and radiation, often pointed towards Earth.

Coalescence is the process by which black holes merge, releasing enormous amounts of energy in the form of gravitational waves.

The Event Horizon Telescope is a network of radio telescopes that captured the first direct image of a black hole in 2019.