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But if you are really worried about legalese, consult a lawyer. Don't simply trust what you read on the internet

In every sane country, you always own copyright on whatever (original work) you create. However, if you write something along the lines of "Copyright (c) <year> <name>. All rights reserved." that is a nicer way of explicitly specifying you keep all the rights to yourself.

That said, this still doesn't fully protect you, since there are countries that don't respect foreign copyrights (as shown by large amounts of fake products originating from those).