Well, it's a mixed bag. Some are extremely true to the original events, but often filmmakers have to make some changes for cinematic appeal. It's not always easy to say exactly how true they are.
Not really. The Rocky movies are fictional works, although they might draw inspiration from real-life elements of boxing and the human spirit of determination.
The 'Saw' movies are not based on actual events. They are designed to thrill and shock audiences with their inventive and often disturbing plotlines, but they have no connection to true stories.
Definitely not. The Scream movies are not rooted in any actual events. They're part of the horror genre that aims to scare and thrill audiences through fictional scenarios and characters.