A bill is a proposal for new legislation or an amendment to existing laws that is presented for debate and approval in a legislative body, such as a parliament or congress. Bills can be introduced by members of the legislature, known as legislators, and must go through several stages, including committee review and voting, before becoming law. If a bill is approved by the majority of the legislative body, it is sent to the executive branch, often the president or governor, for final approval. If signed, the bill becomes law; if vetoed, it may still become law if the legislature overrides the veto with a sufficient majority.