Final answer:
The Québec Pension Plan (QPP) is mandatory for workers aged 18 or older in pensionable employment, fitting within the larger framework of pension insurance and the shifting landscape from defined benefits to defined contribution plans.
Step-by-step explanation:
The Québec Pension Plan (QPP) is mandatory for all workers aged 18 or older who are in pensionable employment. This plan is a part of the broader category of pension insurance, wherein employers contribute to a retirement fund for their employees. Traditional pension plans, known as defined benefits plans, are becoming scarce and are being replaced by defined contribution plans like 401(k)s and 403(b)s. These modern retirement plans are beneficial as they are tax-deferred, portable, and can lead to significant savings without the risk of inflation costs affecting traditional pensioners. By contributing to these plans, employers and employees collectively invest in the future financial security of the workforce.