Ok, so first let's explain how a Parliament works. In most Western countries (short list: Canada, Spain, the UK, Ireland, Germany, Italy, Australia, the Netherlands, Israel, but NOT the USA or France), the executive and the ceremonial head of state are two different people, and the latter is politically very weak and irrelevant*. The executive, however, is appointed in a radically different way than it is in the United States. The Prime Minister and her/his cabinet are selected from Parliament, and they serve at the mercy of Parliament. They can, at any time, be removed by a majority vote of Parliament (called a 'vote of no confidence'). Essentially, this makes the Prime Minister the head of the executive, and the leader of Parliament.

Typically, this also means the government can pass most of its agenda with little trouble. The limit on the executive's power comes in the form of the requirement that elections happen at least once in a certain period of time, and from the restriction of the confidence vote. When the Prime Minister fails to carry a vote of confidence, Parliament has the options of either declaring new elections or of trying to assemble a new coalition of parties and ministers (basically Cabinet secretaries) that will potentially survive a new confidence vote.**

Now that that's explained, let's explain what's going on in Canada right now. Earlier this year, they had their Parliamentary elections. The major contending parties were:

The Conservatives--Also called the Tories, this party was triditionally sort of more a Lieberamanesque sort of moderate conservative/libertarian sort of party. Under the leadership of current Canadian Prime Minister Stephen Harper, it has taken a sharp rightward tilt

The Liberals--the dominant party in Canada for most of its history, lead by Stéphane Dion

the NDP--The New Democratic Party is a leftist challenge to the Liberals

The Bloc Québécois--a generally leftist party that advocates greater autonomy, and at times, outright independence for Quebec.

The elections were held this year with the following results:
Con-143
Lib-77
BQ-49
NDP-37

With the Greens getting 6.7% of the vote but no seats in Parliament. Adding up the numbers will show that the Conservatives do not hold a majority of seats (though they gained in the election), and in fact, only netted 37% of the vote. But, having the plurality of seats, Harper formed a government, and proceeded to govern in the same way that he had since 2004.

Apparently, however, the NDP has decided that they are finally frustrated enough with Conservative rule to actually move against the Harper government, and they have virtually concluded talks with the Liberals (and the BQ, which will, under this deal, vote for the government but receive no Ministers) to vote no confidence in the government, and to install a new coalition headed by a party not in the plurality for the first time in a very, very long time (if at all).

Wow, that was long. Sorry.

*This role can be elected, appointed or heriditary. In the Republic of Ireland, it is the elected position of President. In the United Kingdom, it is the Queen. In Canada, it is the Governor General, who is appointed by the Queen of England and "acts in her interest". Regardless, the role is very weak, and though there are vast formal powers, and even some slight de facto powers, the job is mostly ceremonial.

**As an aside, this jostling is a big factor of how Hitler was ever able to come to power. The Nazis and the Communist party of Germany both had large factions in the Weimar Parliament. You essentially had socialists and libertarians in coalition with each other, an an effort to keep the extremes out of power. These governments collapsed constantly, and it was impossible to get anything done. In an effort to create a government that would survive a no confidence vote, the German President, WWI general Von Hindenburg, thus gave Hitler the chance to try and form a government in order to pursue some stability. Thus, Hitler became Chancellor of Germany. better discussion here