Welcome to the Forums Sven.
Just hang around here for a while and you'll learn everything you need to know.
Quick tip: learn how to use the search feature -- it's one of the buttons on the right side, near the top. That will get you a lot of valuable information without having to wait for other people to reply.
As far as the Benchmade 556 goes, I don't think there's anything especially dangerous about it. I wouldn't throw it when closed, because it might open. See if you can find James Mattis's old list of basic safety rules for knives somewhere online.