Don’t expect a straightforward timeline, because continuity is a mess with the Alien and Predator timelines (even if, as in this list, you choose to ignore tie-in comics, novels, and games). Predator: ...

The classic Alien franchise might have been complete altered if this alternate Ripley ending was released.

A 90s cult classic sci-fi movie ripped off Ridley Scott's Alien with a scene that has an even longer legacy than that.