The first ten amendments to the U.S. Constitution are called the Bill of Rights.
The amendments were proposed by Congress in 1789 and ratified by the states in 1791. They were added largely in response to Anti-Federalist concerns that the new Constitution did not sufficiently protect individual liberties. James Madison introduced the amendments in the First Congress, drawing on proposals from the states and arguments made during the ratification debates.
The Bill of Rights protects freedoms including religion, speech, press, assembly, and petition. It also addresses firearms, searches and seizures, criminal procedure, jury trials, punishments, and powers retained by the people or the states. The amendments were added to the Constitution rather than written as a separate governing document.
A common mix-up is assuming all constitutional rights are in the original 1787 text. Many major protections, including freedom of speech and religion, appear in the amendments instead. The original proposal contained twelve amendments, but the first two were not initially ratified; the next ten became the Bill of Rights.