Anyway, here's a useful article that tries to describe the differences:
http://insects.about.com/od/antsbeeswas ... ornets.htm
The key thing is that all three have yellow stripes. A quick breakdown from that article states:
Even more interesting, and this is something that I did not know at all, is that yellow jackets are the only one that nests underground:In general, wasps can be distinguished from bees by their lack of body hair and thinner, elongated bodies. Differentiating between paper wasps, hornets, and yellowjackets is a bit trickier. All three are types of Vespid wasps, and share certain physical and behavioral traits: narrow wings that fold longitudinally when at rest; larvae reared on dead or living insect prey; nests constructed of recycled wood fibers; and the ability [unlike bees] to sting repeatedly. Paper wasps live in colonies of less than 100 individuals, while both yellowjacket and hornet colonies can number well over 100 Vespids.
So when you're on a block which has both types of nests, hanging nests and underground nests, they are actually two different types of insects, even though they look very similar and most people assume that they're the same thing.Paper wasps build open, umbrella-shaped nests, often found suspended from eaves or window casings on the outside of your home. Hornets are famous for their massive, enclosed nests which can be seen hanging from tree branches or other sturdy perches. Yellowjackets also make enclosed nests, but theirs are found below ground.
What is usually just referred to as a "hornet" (the yellow-striped variety) by North Americans is actually the European Hornet or Vespa Hornet. I always thought that European Hornets were just a type of wasp. Here's some info:
http://en.wikipedia.org/wiki/European_hornet
Very similar to the Vespa Hornet is the Vespula (or Dolichovespula) Hornet, which is what is usually called the yellow jacket. The stripe pattern on the Yellow Jacket is remotely similar to the European hornet, but different when you look closely. Here's some info:
http://en.wikipedia.org/wiki/Yellow_jacket
The type of hornet that I had on my arm today, which is what I always thought was the only type of hornet, is called a Bald-Faced Hornet. Here's some info:
http://en.wikipedia.org/wiki/Bald-faced_hornet
And finally, here are photos of all three. The yellow bands on the Vespula (yellow jacket) seem to wrap right around the bottom, but on the Vespa (European) they don't. Yellow jackets also have yellow legs. That's about all I can figure out for differences.
Vespa/European Hornet:
Vespula/Yellow Jacket:
Bald-Faced Hornet:
And since I'm on the topic, there are lots of types of bees. Here is a common type, the honey bee. Bees are usually quite furry/fuzzy, so it's easy to tell them from wasps if you look closely:
You've probably heard the rumour that bees have hooked stingers, so when they sting you, the stinger gets embedded in your skin like a fish-hook, and it rips out of their body, and they die. And you've probably heard that wasps have straight stingers, so they can sting you repeatedly. Is this true? Party. It is true for honey bees. Other types of bees (bumblebees) have relatively straight stingers and can sting you multiple times. And some types of bees don't have stingers.
And the best new bit of trivia of the day? You have probably heard that only female mosquitoes will bite humans, and male mosquitoes won't? The same applies to bees and wasps!
Here's more information:
http://insects.about.com/od/StingingBit ... ng-You.htm