though I want to know difference between work visa and visitor visa.
Okay few things :
1. There isn't any called "Work Visa". What is there are a Work Permit and a Temporary Resident Visa.
1.a Work Permit is the authorization which allows you to work AND also is the basis of a Temporary Resident Status which allows you to live in Canada temporarily.
1.b Temporary Resident Visa allows you to travel to Canada ie to board a flight to Canada, to present yourself at a Canadian airport etc and ask permission to stay in Canada. Thats all! This visa while is important in getting a Temporary Resident Status, DOES NOT allow you to live in Canada. It only allows you to travel to Canada.
So now what do you see on your passport? That thing is called a Temporary Resident Visa (TRV) and it mentions your category as "Worker" or "W-1". It means you are allowed to travel to Canada for an intention of being a Worker here. The border checking people will then decide to allow you in AND grant you a Temporary Resident Status as a Worker (Which is roughly what a work permit is). If you already have a Work Permit which is not expired, it means you also have a Temporary Resident Status in Canada.
Now coming to Visitor Visa. This is again a Temporary Resident Visa. It allows you to travel to Canada and (possibly) gain status as a Visitor for a time period decided by border official folks. Default is six months.
TL;DR :
Work Visa = Doest not Exist possibly you mean Temp. Resident Visa (Worker, W-1)
Work Permit = Live and Work in Canada
Temp. Resident Visa = Board flight to Canada or Travel to Canada. (Thats why it is pasted on your passport!)
Temp. Resident Visa (Worker, W-1) = Board flight to Canada or Travel to Canada AND ask for an initial work permit at the port / border OR present your existing status supported by your authorization ie your work permit and ask permission to enter canada as a worker. Interestingly, IRCC sometimes also calls this as Visitor Visa for Students or Workers.
Temp. Resident Visa (Visitor) aka Visitor Visa = Board flight to Canada or Travel to Canada AND ask for permission to live in Canada as a visitor for possibly upto six months.
I must mention that : I am NOT a lawyer nor immigration consultant of ANY kind (registered or otherwise or what so ever). I am only telling you what I have read on canada.ca website and based on my personal experience. Any of the above is NOT a legal advice OR immigration advice. If you are in doubt, you should trust a lawyer or an authorized immigration consultant only.