Full Text of the Second Amendment
A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.
Whether this provision protects the individual's right to own firearms or deals only with the collective right of the people to arm and maintain a militia was long debated until the Supreme Court ruled in 2008 that the amendment protected individuals’ right to possess firearms unconnected to any service in a militia. Source: U.S. Senate
Right to Bear Arms: The principal debate surrounding the Second Amendment concerns whether the right to use and buy guns belongs to individuals or only to a militia. Although the courts generally have held that the right applies to individuals, they have permitted the government to limit some rights of gun manufacturers, owners and sellers. Today, questions about the Second Amendment center on bans on assault weapons, mandatory background checks, waiting periods, and other restrictions on gun sales or use.
With the passage of the Fourteenth Amendment and subsequent Supreme Court rulings, states were prohibited from making or enforcing laws that infringe on most of the rights set out in the Bill of Rights.
However, this prohibition does not extend to the Second Amendment. This means that the Second Amendment applies only to actions by the federal government. It does not protect people from state actions that interfere with their right to bear arms. As a result, gun control legislation varies widely among the 50 states. Source: Annenberg Classroom