What are these creatures?

[Life is Wild]

Jumping spiders don't tend to bite people, even if disturbed, so they aren't scary at all. And best of all, they are very exciting to watch because they hunt actively, stalking their insect prey like a lion, creeping up by moving one leg at a time very slowly until they are within pouncing distance...then, of course, they jump on it! They still have silk producing abilities which they can use for rappelling and breaking a fall, but they don't build webs to trap prey, so no need to worry about them making a mess. Let a few live in your windows and they will hunt down flies for you.