A naturalization application is an essential step in the process that an individual embarks on towards becoming a citizen of the United States. The naturalization application, which is also known as the N400 form, gets much needed detail on an individual that hopes to become a citizen of the United States. On this application, the individual will list out what they have been doing in the minimum of five years that they must have lived within the United States including their residency, employment history, and any criminal activity. It's important that an individual be truthful as they fill out their naturalization application because the government will check back on the facts provided throughout the process.