Legislation (or a bill) can have many purposes: to regulate, to authorize, to proscribe, to appropriate (provide funds), to sanction, to grant, to declare or to restrict. Pieces of legislation are usually proposed by a member of Congress, or by the President, whereupon it is debated by members of the Congress and is often amended before passage. Once a bill is passed by the Congress and signed by the President it becomes the law of the land.
A sponsor of a bill is a member of Congress who introduces a bill or amendment and is its chief advocate.
A cosponsor of a bill is a member of Congress who adds his or her name as a supporter to the sponsor's bill. An "original cosponsor" is a member who was listed as a cosponsor at the time of a bill's introduction, rather than added as a cosponsor later on.
114th Congress (2015-2016)
My Cosponsored Legislation
My Sponsored Legislation
113th Congress (2013-2014)