This article is from the The Terminator FAQ, by Karsten A. Loepelmann email@example.com with numerous contributions by others.
The time travel of the Terminator movies is *not* the same as that of the
"Back to the Future" series. Although no one is sure what would happen if you
created a paradox, it is highly unlikely (and goes against the laws of
for our universe) that matter would just disappear into thin air. Time-travel
paradoxes are a lot more complex than that. (See section 6 for more on time
According to the novelization, Judgment Day is avoided; Sarah becomes a
grandmother and John a Senator fighting the Skynet bill in Congress (see
section 1.2.3). Also in the book, the Terminator jumps into the molten pit on
its own--as was called for in an early script draft.