These will be used to identify you as you contribute to the Confluence site. Any notifications from the system will be sent to this email address. Also, if you lose your password, you can have a new one sent to your email address.

Your username will be used to log in to Confluence. This must be unique: for example John Smith could use jsmith. Alternatively you can use your email address as your username.

Finally, choose a password for your account. Pick something you will be able to remember, but that someone else (even someone who knows you well) would not be able to guess.
To make sure you do not mistype your password, you must enter it twice.