I found all this helpful IMVU Information at

Many people have been asking what an IMVU Noob is so I am going to try to explain it to you.

A noob may be a person who is new on IMVU and just wears the same clothing that IMVU equipped your avatar with. This means anyone with a guest name who still wears the starter outfit that was given when they are no longer a new avatar. 

These people will enter chat rooms trying to get free stuff form you or will sit in the corner causing trouble with other avatars. If you see a person like this in your chat room it may be a good idea to kick them out.

However, not all the time will it be a person with a guest name. A noob could also be a person who is very disrespectful and ignorant acting in the Metaverse. These people don't want to learn the basics of the metaverse but rather just cause disturbance between other users.

You have the right to ban anyone from your chat rooms; however, make sure there is a good reason to ban them. Even if they have a guest name they may be a cool person to hang out with and get to know.