The Canada Pension Plan (CPP) retirement pension is a monthly, taxable benefit that replaces part of your income when you retire. If you qualify, you’ll receive the CPP retirement pension for the rest of your life.
To qualify you must:
Valid contributions can be either from work you did in Canada or as the result of receiving credits from a former spouse or former common-law partner at the end of the relationship.
With very few exceptions, every person over the age of 18 who works in Canada outside of Quebec and earns more than a minimum amount ($3,500 per year) must contribute to Canada Pension Plan (CPP). If you have an employer, you pay half the required contributions and your employer pays the other half. If you are self-employed, you make the whole contribution.
Read more here.
Read about Canada’s social security agreement with other countries here.