Email/User Name

[Alwin Alcott]

you can change the email adress at your accountpage.

You can change your display name once a week, but not change the username.

You also can not hide the username for other people thats a per user viewer setting.

You of course always can open a new account with a more desirable name.

[Alwin Alcott]

you can change the email adress at your accountpage.

You can change your display name once a week, but not change the username.

You also can not hide the username for other people thats a per user viewer setting.

You of course always can open a new account with a more desirable name.

[Rolig Loon]

Your username (login name) is permanent and unique.  Your Display name is an optional convenience, like a nickname in RL.  If you use a Display name (many people don't), you can change it once a week if you want. 

You can always turn off the Display names in your own viewer if you find them confusing.  I always have them switched off in mine, and so do most people I know, because they are confusing, as you pointed out.  Many people use totally illegible characters in Display Names, and they change them frequently. You can't depend on Display names to know who you are talking to.

[Syo Emerald]

Your username is the only thing other people can identify you as you. So no, its not possible to hide it for others or change it to something else. Some people may even be so annoyed by all the stupid displaynames, that they chosed to only have usernames displayed.