Bill Definition:

A first draft and proposed law or statute which has been formally tabled before a legislative assembly for consideration.

A bill becomes legislation or a statute when the appropriate parliamentary or legislative assembly has approved it by holding a vote and in the result, giving it the requisite number of approval votes.

Each time a bill is put to a vote, it is called a "reading", as in First Reading, etc., until its final reading, such as "third reading", at which time it is passed and awaits coming into force (as a statute or law) upon a date of the government`s choosing, unles the bill (now a "statute") specifies a date at which it comes into force.

In the United States, a bill requires the approval of both branches of the US Congress (the House of Representatives and the Senate) and the signature of the President to become law.

When a bill is introduced in Canada's House of Parliament, it is assigned a number based chronological order of introduction in its House of origin except that government bills are numbered  from one to 200 while private members' bills start from #201.

See also bill of exchange, bill of lading and bill of attainder.