Quote from: Zlantann on Today at 12:07:51 PM

This forum has no policy on name selection. This means that prospective members are free to choose any name they want in the course of registration.

This is not totally accurate. There are some reserved words you can't include in your username when registering a new account. Some of those words are "Satoshi", "theymos", "bitcointalk" and probably all staff usernames. Obviously this restriction exists to prevent impersonation attacks.

Quote from: tranthidung on Today at 03:37:03 PM

Username can be changed by

Yourself if you are the VIP member with 50 BTC donated to the forum. You can do it by yourself.
Admin

I just want to add that staff members can change their display names (not usernames) and probably many members do not realize there is a difference between the two.