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The Grandfather Paradox involves going back in time and accidentally or intentionally preventing your grandparents from meeting, thus preventing your own birth. This raises the question of how you could have traveled back in time if you were never born. Example: 'The Terminator' film series, where the protagonist is sent back in time to protect his own existence by ensuring his parents meet.

The Multiverse Paradox suggests that each time a traveler alters the past, a new parallel universe or dimension is created to account for the change, rather than changing the traveler's original history. Example: 'The Man in the High Castle' by Philip K. Dick explores alternate histories, which can be seen as resulting from different timelines in a multiverse.

The Ontological Paradox is a subset of the Bootstrap Paradox, where an object or piece of information creates a never-ending cycle of existence. Example: In 'Somewhere in Time', a man receives a watch from an elderly woman, which he later gives to her in the past when she's younger, creating an infinite loop of the watch changing hands.

The Bootstrap Paradox, also known as an ontological paradox, occurs when an object or information is sent back in time and becomes the cause of itself in an infinite loop. It lacks a clear point of origin. Example: In 'By His Bootstraps' by Robert A. Heinlein, a character receives a notebook from his future self, which he later writes and intends to give to his past self.

The Novikov Self-Consistency Principle states that any actions a time traveler makes must be consistent with the history that already exists, thus precluding any paradoxes. In essence, you can't change the past because you've already not changed it. Example: 'Harry Potter and the Prisoner of Azkaban' follows this principle when Harry and Hermione time-travel.

A Predestination Paradox occurs when a time traveler's actions in the past cause events to unfold in such a way that they lead up to their original departure to the past, creating a causal loop. Example: 'All You Zombies' by Robert A. Heinlein follows an individual through a series of time travel events that lead to his own birth.

A Temporal Paradox is a broader term for a paradox that arises when a discrepancy between time and events creates a logical contradiction, such as changing the past or information emerging from nowhere. Examples: 'Doctor Who' often deals with temporal paradoxes during its time-traveling adventures.

A Causal Loop, also known as the causality loop, is a theoretical proposition in which a sequence of events is started by the consequence of a later event, essentially a loop where cause and effect run in a continuous cycle. Example: 'Looper' features hitmen who are sent their future selves to assassinate, creating a loop in time.

The Twin Paradox arises from Einstein's theory of relativity, where one twin who travels at near-light speed ages slower than the other who stays on Earth. While not a time travel paradox in the usual sense, it deals with differing time experiences. Example: 'Time for the Stars' by Robert A. Heinlein uses the Twin Paradox as a central theme, with twin brothers experiencing time differently due to space travel.