How does Canada's electoral system work?

National elections in Canada are conducted much like
national elections in Great Britain.  Voters in local ridings elect members to the House
of Commons.  The House of Commons then selects a Prime Minister from among its
members.

Elections in each riding are conducted using a
plurality system.  There is only one member from each riding and whichever candidate
gets a plurality of the vote (more of the vote than anyone else) wins.  The members of
the House of Commons then determine who will be the Prime Minister.  The PM is generally
the leader of whichever party can gain a majority of the seats in the House of Commons. 
He or she is not elected on a nationwide basis like the President of the US.  Instead,
the PM is simply a member of the House of Commons, elected by his or her riding, who is
then selected as PM by the House.