This is the country-code top level (ccTLD) domain for the European Union.  

This domain is available for European Union citizens, independently of their place of residence or any natural person, company or organization residing in or established within the European Union, Iceland, Liechtenstein or Norway.

You can check Domain availability here.
The Terms and Conditions can be found here.
IDN is supported (Special characters like å, ä, ö, more info here).
Blocked and not-allowed domains here.
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