In a Parliamentary democracy, a minority government is formed when one party controls a plurality, but not an absolute majority, of the seats in the parliamentary assembly. The governing party thus has to seek cooperation from one or more opposition party in order to pass legislation. They can fall if the other parties combine against the government in a vote of no confidence.
The first two federal governments of Canada led by Prime Minister Stephen Harper (those formed after the 2006 and 2008 general elections) were minority governments.