Uscis
In short
USCIS is the United States government agency responsible for managing lawful immigration and naturalisation processes. It handles applications for citizenship, green cards, and work permits.
In plain words
This agency checks if people are allowed to live or work in the USA. They process paperwork for people moving to the country or becoming citizens. They make sure everyone follows immigration laws.
A simple example
A person living in America applies to USCIS to change their status from a temporary student visa to a permanent resident. The agency reviews their documents and conducts an interview to approve the request.
Why it matters
It controls who can legally enter and stay in the United States. Without their approval, people cannot obtain the legal rights needed to work or live permanently in the country.
Easy to mix up
Do not confuse USCIS with CBP, which focuses on border security and checking travellers at ports of entry.