HST = Harmonized Saled Tax.
Before July 1, 2010, We Ontarions (from Ontario province) used to pay two taxes: GST of 5% and PST of 8%.
However, basic neccessities were exempted from PST such as electrcity bill, gas bill, hair cut, gasoline and etc.
Now Both PST and GST have been combined and we pay 13% tax on pretty much everything. Which actually increases the cost of purchase for us.
Hope that helps. 