Green card is a legal permanent residence status given to a foreign individual by US government. Basically, green card allows immigrants from all over the world to work and live in the US with the same rights of US citizenship except for right to vote up to 5 years. After 5 years, a person can apply for US citizenship.
There are some legal ways to eligible for a green card.
1) Green Card through employment in the United States
2) Green card through immediate family staying as citizens in US.
3) Green card through marriage to a US citizen.
Addition to the above options for obtaining green card, there are some special cases that allow individuals to obtain a green card.
The special cases are as follows:
1) National Interest Wavier
5) Specialized Skills
Green Card through employment in the United States:
In this case, the employer of the foreign nation must sponsor that individual. Once the employer sponsored the individual may make application for a green card. It is a much faster process for the individuals with more education or specialized job skills.
Green card through immediate family staying as citizens in US:
In this case, if a foreign individual has a family member such as parent or child that is an US citizen, then they are eligible for a green card. If a parent of a foreign minor child is an American citizen then that child is automatically and immediately eligible for a visa.
Green card through marriage to an US citizen:
Foreign person can eligible for a green card is through marriage to a United States citizen; however, the American citizen must stay in the United States. Once the person has obtained their green card they can apply for permanent residence.
There are some other special ways to apply for green card on time basis.