Originally Posted by Elfwreck
Everyone copyrights unless they specifically release their works into the public domain.
Do you mean, "do you register your works with the US Copyright Office?" (Where they have a backlog of 18 months or more for registrations?)
In an effort to stop a little misinformation, the moment you create the work you own the Copyright of it. One way of showing a date of copyright is to mail the work to yourself, however it hasn't been shown if that is a way of protecting your work in a court of law.
To legally enforce that Copyright it is a good idea to file it with your Countries Copyright office. At this time the US Office turn around time is 90 days.