Simulated view of a black hole in front of the Large Magellanic Cloud.
Simulated view of a black hole in front of the Large Magellanic Cloud.

To quote from Wikipedia (again):

A black hole is a region of space in which the gravitational field is so powerful that nothing, not even light, can escape its pull after having fallen past its event horizon. The term "Black Hole" comes from the fact that, at a certain point, even electromagnetic radiation (e.g. visible light) is unable to break away from the attraction of these massive objects. This renders the hole's interior invisible or, rather, black like the appearance of space itself.

Black holes in fiction are some of the trickiest things to analyze, because it's often difficult to determine if it is a "real" black hole, or just some kind of black hole-ish void. Since black holes in fiction rarely conform to the actual physical properties of their real - life counterparts, this is usually a problem.

An actual black hole, in a fictional context, is generally considered to inescapable to any entity that does not have either reality warping, FTL speed, or time travel. Small black holes produce gravitational shearing forces capable of tearing apart any kind of matter at the subatomic level (of course, in fiction, there are exceptions). Black holes cannot be destroyed with brute force, because they will simply absorb all energy/matter thrown at them, and grow larger. They are capable of easily destroying planets and stars (although with small black holes, it might take a while). Black holes do decay over time due to Hawking Radiation, so if you leave a black hole alone and don't feed it anything, it will eventually grow smaller and explode (this type of detonation is a 100% efficient mass - to - energy conversion, with more potential power than a nuke or antimatter explosive). Tiny black holes with masses less than a few trillion tons would evaporate nearly instantly. Black holes with higher masses last much longer - a black hole with the mass of the sun, for example, would last for billions or trillions of years before evaporating. Black hole based attacks are often considered to be OHKs.

Examples of characters and entities that can create/manipulate actual black holes:

- Culture ships (nanohole bombs)
- Buster Machine #3 from Gunbuster
- Nono from Diebuster
- The Time Lords and several races and technologies from Doctor Who
- The Silver Surfer and other Heralds of Galactus, from Marvel
- Several technologies in the Tenchiverse, including Zinv from Dual! Parallel Trouble Adventure
- Solar, Man of the Atom from Valiant Comics
- R'amey and other specialized Green Lanterns from DC Comics
- Primus from Transformers
- Several races, including Humanity, from Xeelee Sequence by using technology
- Toa of Gravity from Bionicle can create small black holes, but they cannot control them
- Jack Rakan and Albireo Imma, from Negima
- Asdrubael Vect from Warhammer 40,000 used a black hole contained inside a box to assassinate one of his rivals.
- Some Space Pirate ships were equipped with weapons that generate micro black holes (They use this to wipe out the planetary shielding on Zebes). Samus is also supposedly able to create a much weaker black hole with certain weaponry
- X from Mega Man X

Examples of characters and entities that can create/manipulate pseudo-black holes/voids:

- Cerberos from Heroic Age
- Blackbeard from One Piece
- Chinmei from Samurai Deeper Kyo
- Ideon from Space Runaway Ideon
- Ede Ee from Bastard!!
- The Rift Ripper from the Ratchet & Clank video games
- Miroku from Inuyasha
- Deoxys and a few Psychic types from Pokemon
- Vanilla Ice from Jojo's Bizarre Adventure
- Garlic Jr from the Dragon Ball Movies
- Luke Skywalker (EU) from the New Jedi Order and onwards.
- Magus from Chrono Trigger
- Reiji Kageyama from Gate Keepers
- Vash the Stampede from Trigun
- Richard Guyot, Sho Fukamachi and a few other Zoalords from The Guyver (left unchecked though, their pseudo black holes become real ones, though they wouldn't be able to control it)
- In Macross Frontier, the Dimension Eaters and MDE weapons work akin to black holes but based on Fold Space technology.
- Garbagemon from Digimon

See also:
- White hole
- Eternal Black Hole