How does the Bill of Rights work?

Answer 1

It is part of the US Constitution - it is applied by the courts

Answer 2

the bill of rights is the first 10 amendments to the constitution. they are certain things that the FEDERAL govenrment promises not to do. for example, restrict speech.
however, origingally the bill of rights was ONLY the FEDERAL government. Your state government was not bound by the bill of rights.

THEN
the 14th amendment came along, and through many supreme court rulings, that court interpreted the "due process" clause to give the same protections the bill of rights did. so they did what is called, "incorporated through the 14th amendment"

so now if someone asks you why Pennsylvania cannot restrict your free speech, your answer would be because of the 1st amendment which has been incorporated to the states by the 14th amendment. works only on amendments 1 - 10.
if its the federal gov't trying to infringe upon one of these rights, then its just that amendment that keeps them from doing it.

historically the bill of rights was not going to be included. they had to add it on for political reasons. there was one group of people that said those 10 things were inherent in the constitution itself and to add the bill would just to be saying it twice, but the other group wasn't quite so sure, so they asked for these things to be specifically spelled out, thus the bill of rights. but that opens the question, is it only these 10 things the government can't do because thats all thats specifically said, or is the bill of rights just sort of a list of examples?

the formation of our country is amazingly complex, and even the guys writing the constitution didn't think that it would last more than 50 years. yet they were able to write a document and fashion a government that is so resilient that it has molded and fit into our society. this is a great subject and not boring at all; you should study up, because what i've said is merely the tip of the iceberg

Answer 3

The Bill of Rights are the first ten amendments to the Constitution. As such, they "work" the same way any part of the Constitution works.
They act as the Supreme Law of the land, any law made in conflict with the bill of rights is "unconstitutional" and will be struck down by the Courts.

That said, the interpretation of the Bill of Rights (and the Constitution) is done by the Courts. Many of the amendments are much more complicated than the "plain" text would make it seem.