The U.S. immigration system was created in accordance with current immigration law. It is regulated in detail and designed to serve the national interest of the United States. Through this system, U.S. citizens and lawful permanent residents are able to reunite with relatives, and U.S. employers are able to hire highly skilled foreign professionals. Current immigration laws also allow for support and protection of the rights of refugees from around the world. The current immigration system is built on U.S. constitutional principles. As such, immigrants have full civil rights and freedoms equal to U.S. citizens, except for the right to vote and be elected, to hold certain positions in the government, and limited rights to apply for immigrant visas for persons who are relatives.
Legal Permanent Resident is a person who is not a U.S. citizen but who holds an immigrant visa or who is in the process of adjustment of status and citizenship. Legal Permanent Resident status is evidenced by a Green Card, which is a permit to live and work permanently in the United States.
Nonimmigrants are citizens of other countries who are permitted to enter the United States for a limited period of time on a temporary (non-immigrant) visa. Nonimmigrants include students, tourists, seasonal workers, business people, executives, and diplomats.
Individuals in the United States on temporary (non-immigrant) visas have limited rights as compared to U.S. citizens and lawful permanent residents. The amount of rights a temporary resident has depends on the visa category.