Avatars are the images which are displayed below your user name in posts and messages. You can use one of the forum avatars or use one of your own. These can be uploaded to the forum or hosted elsewhere.
If you choose to use your own avatars, then make sure it is no bigger than 100x100px else they will be resized, reducing their quality.
To select an avatar, sign in, click on "PROFILE" at the top of the page and then click on the "Forum Profile Information" link on the left. Here you can choose an avatar from the gallery, or you can upload an avatar or link to one elsewhere.
Avatars
Avatars
The one and only!