The Senate is the upper house in Canada’s bicameral parliamentary democracy.The original Senate, created in 1867, had 72 seats, but more seats were added as the country grew.The Constitution now directs that the Senate have 105 appointed members.
The Senate was created to counterbalance representation by population in the House of Commons. In recent years, the Senate has come to bolster representation of groups often underrepresented in Parliament, such as Aboriginal peoples, visible minorities and women. The Senate was also intended to provide Parliament with a second chance to consider bills before they are passed. Senators may pass bills, propose amendments to them or vote to defeat them.
(Source: Senate of Canada)