When you visit Canada, you may enter the Country with a visitor, student or work visa, yet it is your permit and its duration that makes you eligible to reside in Canada over 6 months in a year.
Most common permits you will initially hold are either a student or a work permit. Whether you are solely a tourist visiting Canada, a student or work permit holder, you are considered to be “temporary resident” until the day you become a Permanent Resident. Therefore, even when your permit is renewed (from a study to a work permit, from a work to a newer work permit), you will be applying for a Temporary Visitor Visa to make yourself eligible to re-enter the Country.
There are cases where one receives a visitor visa with an expiry date up to 10 years (in accordance with your passport expiration date) even though application was made for a work visa. Please be reminded that a visa enables your entry to the Country, where your permit determines your status and eligibility requirements for employment within Canada.
Disclaimer: Please be reminded that context above provides general information and every individual must be evaluated case by case in terms of immigration pillars in Canada. To ensure a healthy immigration status, you must consult a professional as federal and provincial governments may have different requirements or may change applications temporarily or permanent.