USA Simple Civics · Immigration

How U.S. immigration works

Immigration means moving to another country to live. U.S. laws set rules for who can enter, stay, work, and become a citizen.

Start with the basic words below, or choose a topic to learn more.

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Paths & rules

How can people move here?

Learn about legal paths, border rules, and what happens when someone breaks immigration laws. See immigration and deportation numbers.

Explore laws & enforcement → Citizenship

How does someone become a citizen?

Learn who can apply, what steps they take, and what becoming a U.S. citizen means.

Explore becoming a citizen → Jobs

How do immigrants get work?

Learn about permission to work, hiring rules, and the checks employers must make.

Explore work & employers → Benefits & taxes

Who can get help, and who pays?

See who can get food, health care, or housing help. Compare state programs, tax payments, and public costs.

Explore public benefits → History

How have immigration rules changed?

Explore immigration laws over time, Ellis Island and Angel Island, and how leaders have debated immigration.

Explore immigration history →

The basic words

Six terms you’ll see on these pages

Visa
A document that lets someone travel to a U.S. entry point and ask to enter. Border officers decide whether the person may enter. Different visas have different rules.
Green card
Proof that someone has permission to live and work in the United States permanently. A green card holder is not yet a U.S. citizen.
Citizenship
Being a legal member of a country. People can be U.S. citizens at birth or become citizens later. The process of applying to become a citizen is called naturalization.
Refugee
A person approved to come to the United States for protection. They generally apply from outside the country because they face serious harm for a reason covered by the law, such as their religion.
Asylum
Protection that someone asks for after reaching the United States or a U.S. entry point. They must show that they face serious harm for a reason covered by the law. Applying does not mean they will be approved.
Undocumented
A word used for someone without current legal immigration status. They may have entered without permission or stayed after their permission ended. Different situations can have different legal outcomes.

Each permission has its own rules. Permission to visit, permission to work, a green card, and citizenship are different. A person’s status can also change over time.

These are short definitions. The topic pages explain the rules and exceptions in more detail.

Learn more

Official starting points

Basic definitions reviewed October 16, 2026. Follow each topic page for its sources and review dates.