There is an immigration form for almost any situation in the Canadian immigration system. Finding the proper one can be a bit of a process. Generally, the most popular immigration forms have to do with either applying for Permanent Residency or Citizenship, but these are just very general categories and there are much more specific forms.
Below are the three most popular Canadian immigration forms:
This form is used to file for entry in the Federal Skilled Worker Program. This program has recently been revamped for 2013 to be more inclusive of skilled tradespeople. Previously it was geared more toward accepting people with higher education. The problem with the previous system was that doctors or researchers entered Canada but were unable to find jobs in their positions, and eventually became taxi drivers or shop workers.
The Canadian government would of course prefer immigrants to go into the profession of their particular skill and experience and considering the recent need for skilled workers all over Canada, and particularly in the west, this program has changed to accommodate them.
The official name of this form is the Application for Permanent Residence from within Canada: Spouse or Common-Law Partner in Canada Class. This application is used for spouses or partners of Permanent Residents in Canada who themselves are temporary residents. They can apply using this form for Permanent Residency. Same-sex marriages and common-law relationships are recognized for this form as well.
This application is used for Permanent Residents to become citizens of Canada. You can apply for citizenship as an adult if you are at least 18 years old, lived in Canada for at least three out of the past four years, are competent in either of the official languages and be well versed in Canadian culture and government. Criminal issues may preclude you from citizenship.