What does shall not be infringed mean in the second amendment?

It means United States Citizens, have a god given right to keep and bear arms/guns. And the government CanNot make any Laws to infringe this right. Like freedom of speech? Reality: The FBI does a background check before you can buy a gun. You cannot carry that gun anywhere, you'll get arrested and your property stolen. If you're lucky enough to live in a state with consealed carry it's expensive and likely will not issue the permit. See Above-the sad truth is the second amendment is worthless, as thousands of laws INFRINGE on our right.
It means that the second amendment to the Constitution gives all citizens of the United States the irrevocable right to obtain, keep and bear arms, and this right shall NOT be infringed upon by ANYBODY.