Naturalization is the act by which a foreigner may obtain a U. S. citizenship. For this an individual must fulfill the necessary requirements assigned by Congress in the Immigration and Nationality Act. After the procedure is passed a person will get different opportunities. These are right to vote, ability to travel freely across US borders, obtain a citizenship for children, become officially employed, become an elected etc.
A foreigner may submit an application if he or she refers to particular categories and prove the belonging to an eligible one.
You may file a form if you have a qualifying service in the U.S. Armed Forces. If an applicant has served in the United States Armed Forces during war, that individual may obtain citizenship without first becoming a permanent resident.
Also, a child may submit an application whether his or her parent is a United States citizen if the child was born outside the country or is outside for a certain period of time.
You can search through other categories if none of the above mentioned fits your characterization.
Have a look at USCIS Policy Manual Citizenship and Naturalization Guidance and A Guide to Naturalization for more detailed information.
Check if your parent is U.S. citizen. In this case you don’t need to apply for this procedure.
First of all a person needs to fill Form N-400 out. It is also known as an Application for Naturalization form. An applicant should download the form and pay attention to the provided instructions.