An example of a United States Permanent Resident Card, commonly known as a "green card."

What is a green card? Here’s what you should know

A number of people allowed to live indefinitely in the United States were detained at airports over the weekend after President Donald Trump signed an executive order temporarily banning those from seven Muslim-majority nations from entering the country.

Known as a “green card” due to the ID’s once and current color, it’s formally called a United States Permanent Resident Card.

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The identification card granted by the U.S. Citizenship and Immigration Services (USCIS) allows a foreign national to live and work permanently in the United States.

Not to be confused with a visa, which allows a person to travel or stay in the United States for a specified length of time and for a specific purpose, a green card allows the holder to live and seek employment in the United States indefinitely, sponsor immediate relatives, and work toward citizenship.

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According to USCIS, a person may be eligible to immigrate to the U.S. based on certain criteria:

» Through a qualified family member with preference given those who are immediate relatives of a U.S. citizen

» Based on a job offer or employment weighted toward those with extraordinary abilities, teaching and research credentials, and certain multinational executives and managers

» Through refugee or asylum status

» Other programs and categories such as a diversity program known as the Green Card lottery, and Afghan/Iraqi translator

Applicants may be ineligible due to criminal, security, or certain health-related reasons.

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