Some Wikipedia pages are useful. Some are interesting. And some are laden with awesome, like the entry on Predator. It’s full of awesome information like:

• The water and mud Schwarzenegger had to swim through was full of leeches.
• The Predator’s blood was made out of glow sticks and lube. (Yes, that kind of lube.)
• Peter Cullen is the voice of the Predator. That makes the Predator and Optimus Prime, like, cousins.
• Schwarzenegger wouldn’t do it until it was rewritten as an ensemble movie. He thought it would be boring if it was just him.
• The script was written after filmmakers joked that Rocky had nobody left to fight, so he’d need to take on aliens.
• Jean-Claude Van Damme was supposed to play the Predator, but he was smaller than the commandos, and whined about not having his face on camera and the suit being too hot. He was scrapped for a 7′ actor who could look scary and didn’t complain about everything.
• Principal photography halted for two weeks so Schwarzenegger could get married and go on his honeymoon.

These are things that are important to know.