If you are interested in using/creating an avatar in order to comment here on WordPress, you can use Gravatar. Gravatar is a site that allows you to create one avatar and use it at numerous websites, as long as you’re using the same e-mail address at the different websites. Avatars help the discussion by connecting your username to a picture. Sometimes those pictures are more recognizable than your username. Plus it’s a way to express yourself a little bit. It’s very easy – log in, upload your picture, and you’re done.
Here’s the Gravatar website itself so you can sign up and create your avatar: