Since its inception, 27 Amendments have been added to the Constitution. The first ten Amendments are Known as the Bill of Rights They were proposed by James Madison who eventually become the fourth president of the united state  Amendments are changes or additions to the U.S Constitution. These changes can occur in two different ways. First, an Amendment can be added if two -thirds of both the U.S. House of Representatives and Senate approve the change  Then , three fourths of legislatures of the 50 state must vote to approve the Amendment.The second way to amend the constitution is if two -thirds of the states petition by a two -thirds majority . One example of constitutional Change was the ratification of 19th Amendment in 1919,Which gave women the right to vote. The last major challenge to the Constitution was in 1972 with the proposed Equal Rights Amendment. however , it failed to receive the required number of votes from the states