Function

• The process of obtaining a green card is designed to register and classify immigrants arriving in the United States. The U.S. uses a quota system to regulate the types of workers and national origins who can legally enter the country each year. The green card is proof that an immigrant has pursued the appropriate legal channels and can protect him from deportation.
  
  

Benefits

• Having a green card entitles its holder to many of the rights that citizens take for granted. It is, in fact, a step on the path toward eventual citizenship. The green card entitles an immigrant to lawfully live and work permanently in the United States. An immigrant can travel abroad for short periods of time and petition for his spouse and unmarried children to also obtain a green card. Except in cases where the green card is issued with conditions, they are permanent and do not expire.
  
  

Identification

• Despite the term, "green card" has not actually been green since shortly after WWII. The current format was introduced in the 1970s and, though appearing in several different colors, has never been green. The name persists through popular usage, nevertheless, due to the fact that the original Alien Registration Receipt Card was, in fact, green. Most green cards are currently printed on yellowish-white paper.
  
  

Types

• Legal residence, as evidenced by the green card, can be obtained in various ways and with various limitations. Most green cards are issued through sponsorship by a presumed future employer. Immigrants can petition for a green card on the basis that they are qualified to do specific types of work, and are subject to the quotas regulating these types of employment. Many immigrants obtain their legal residency by the petition of a relative who has achieved citizenship or has permanent legal residence status. Residence through marriage is granted on a two-year conditional basis, before the end of which a petition to remove the limitation must be filed.
  
  

Considerations

• Because of the immigration quotas, obtaining a green card can be a lengthy process, taking several years in cases of countries with high levels of immigration or low priority work skills. Every year, however, the U.S. issues up to 50,000 green cards through a lottery system open to persons born in countries with low immigration rates. This lottery system is an attempt to increase diversity and encourage immigration from less common sources.