Payment networks
Visa, Mastercard and Amex are the rails your payment travels on, not the companies setting your rewards or interest rate. That's your bank.
Visa
The most widely accepted payment network in Canada.
50 cards
Mastercard
Acceptance effectively identical to Visa, worldwide.
39 cards
American Express
Both a network and an issuer: strong rewards, narrower acceptance.
16 cards
For the full comparison, read Visa vs Mastercard: what's the difference?