There are no hard and fast rules for choosing a username, other than that it must be unique and should be relatively easy to type. Taking a few minutes to choose a good username is worthwhile, since your username can't be changed later, and is used in many ways such as accessing your scratchpad, sending you messages, and referring to you in posts. Choose wisely.
Consider that your username is one of the first things other Perl Monks will know about you. What sort of a message do you wish to send? Advice you offer with the username "CompleteMoron" may not be taken too seriously! Likewise, choosing "PerlNewbie" as your username is also ill advised, unless you plan on remaining a newbie forever. People don't name their newborn babies "Born Yesterday". They pick names which will last a lifetime. Give yourself a little credit; you won't always be a newbie, will you?
How easy is your username to remember and type? When people want to send you private messages, or address you or mention you in the chatterbox or in postings, they will have to type out your username. For this reason, usernames should not be too long, and should avoid punctuation and other odd characters HaX0r-$TyL3 names are also difficult for people to remember and type — and won't impress the Monks anyway. So take a few minutes to choose your username carefully, and avoid potential frustrations later.
Some names are "reserved". The following cannot be used as usernames:
Also, there are some technical restrictions on valid usernames, including (but not limited to) the following:
If there is a problem with the name you're trying to register, PerlMonks will let you know, and ask you to select a different name.
to the PerlMonks FAQ
To create a new user on PerlMonks, we need a smattering of information:
When your account has been created, you will receive an email at your given address, from firstname.lastname@example.org, containing your randomly-generated eight-character password. When you have logged in with this password, you may proceed to your Profile and change it to something else.
We are not going to send you junk email "member updates", sell your address to spammers, or display your email address for people to see. This email exists so that you can receive your password, and/or retrieve it if you forget. There may be future email functionality, which you will have the option to turn on from your user settings page.
Once you have a PerlMonks account, there are some rules you should be aware of; please read Site Rules Governing User Accounts.