BugGuide.Net is a useful website that helps users identify bugs. It also provides information about all sorts of bugs if you're interested in learning more about them. Today, I learned that dragonfly nymphs swim by breathing water in and out of their bums. They "breathe through gills in rectum; the transfer of water in and out of the rectum is used for propulsion underwater".
"We are an online community of naturalists who enjoy learning about and sharing our observations of insects, spiders, and other related creatures.
We enjoy the opportunity to instill in others the fascination and appreciation that we share for the intricate lives of these oft-maligned creatures."
There are a few different ways to identify bugs on the site. You can submit a photo of a bug here, and eventually it will be posted on the guide with information about the specimen in question. You can also use the "clickable guide" on the left hand side of the page to try and identify the bug yourself using information provided by the site. Make sure any photos you upload are high quality.