• Permanent Residency in the US.
  
• A Work permit to work anywhere in the US.
• Easy entry and exit without a visa or ESTA.
• Eligibility for Medicare benefits and other government assistance after 5 years as a Green Card holder.
• The right to study at a U.S. university at a cost up to 80% lower than without a Green Card.
• Elegibility of federal loans for students.
• Crisis security: Green Card holders are usually not affected by travel embargoes.
• Uncomplicated obtaining of business and commercial licenses.
• Family members (spouse and unmarried children under 21) are automatically eligible for a Green Card as well.
• Application for US citizenship is possible after 5 years as a Green Card holder.

A Green Card does provide rights like permanent residency in the US, easy entry to the US and the ability to work in the US.
However it does not allow to run for public office, vote in a U.S. election, to work in a federal government job or to travel abroad for an unlimited time.