Weapons have been used since the first moment man figured out he could kill another man (or an animal) without using his hands. But the truth is, as much as we all are aware of modern and historical weapons (swords, cannons, and so forth), how much do we REALLY know? Well, unless you are schooled on it, not a great deal.
Which makes this animated history of weapons that much more interesting.
[H/T to LaughingSquid]