Imagine you're at the zoo, out in a very nice day hanging out with the family, when you decide to visit the gorilla section. Now, imagine your day of happiness turn into an absolute moment of horror when an angry gorilla charges towards the glass and cracks it.

A family, just minding their own business and wanting to see some cool animals, got a taste of that horror when they recorded a Silverback Gorilla angrily charging towards the protection glass. What's terrifying is that the gorilla just seems to snap (he was all peaceful looking in the initial moments) and throw himself into the glass.

So advice for next time -- just waive and maybe take a super quick picture and then rapidly move on.