What is the difference between N-400 and N-600?

Form N-400 (Application for Naturalization):

• For adults applying for citizenship
• Must meet eligibility requirements (5 years Green Card, etc.)
• Requires interview and test

Form N-600 (Application for Certificate of Citizenship):

• For children who automatically became citizens
• Child must have U.S. citizen parent and meet requirements
• No test or interview required
• Just documents citizenship that child already has