Once you have registered, or if you are returning to a site, you can login to the site. In the menu bar on the forum you will find an image/text that says "Login". If it says "Logout" you are already logged in. This can happen if you've already logged in before and chosen to have the forum remember who are you are. This places a cookie on your system. Once you choose "Login" you will be prompted for your user name and password. If the combination is correct you will be allowed to navigate the forum as a user, rather than a guest.
If you're trying to login to the forum but you forget your password or have lost it, you can retrieve it using the lost password tool. On the login screen, next to the username field, it says "Forgot password?" Click this to be taken to the "forgot password" form. Enter your username on this screen and press the Send button. Your password will be sent to the email address registered to that username.
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