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Senate Bill from WikiPedia:

A bill is a proposed new law (or a proposed amendment to an existing law) introduced for debate within a legislature. Even after a bill has been passed by the legislature, it is still formally called a "bill". Once a bill has been formally approved by the executive (in presidential systems) or the formal head of government (in parliamentary systems) and consequently become law ("adopted"), it is called an "act", but the two terms are often used interchangeably in popular usage (or some moments of scholarly imprecision). In the United States, bills have a sponsor (also called "introducer") and sometimes cosponsors. In parliamentary systems, most bills are introduced by the government, and a bill introduced by an individual member of parliament is called a "private member's bill" or (individual MP's) "legislative motion".

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