According to what I've read, hornets are much more aggressive than wasps. Hornets and yellow jackets are the more aggressive of the flying insects that sting. They're also capable of multiple stings without losing their stinger, which may be why they tend to be more aggressive.
Bees (both honey and bumblebees) and wasps are much less aggressive, and they normally won't attack unless the hive or nest is threatened. Last year, I had several wasp nests around the eaves and windows. I had wasps land on my arm and take right off again after a few seconds. I guess they decided I wasn't too appetizing
I got stung a lot as a kid. 95% of the stings were from hornets and yellow jackets. I've never been stung by a honey bee. Once by a bumblebee, and that was my fault. Once by two wasps and it was because I stepped into their nest while looking for raspberries.
All of the times I've been stung as an adult were from yellowjackets.