2.2 messaging and notification
This part of the settings is meant to allow you to chose what notifications you receive, who you would like to mail you, ...
You can select if you would like to receive a private notification if anyone replies to any of your threads or posts.
You can select the option to receive a email ( on the email account you used in your profile ) as notification if anyone replies to any of your threads or posts.
You can select to save any of your sent messages and the replies to it so you can keep track of anything important discussed in mail.
You can select to get a notification if someone quotes you in their post.
You can select to get a notification if someone visits your profile page ( the page itself only shows the last visitors, so if you get many visitors this might come in handy ).