Canada Express Entry is dynamic, Initially you have to create a CIC account than Express Entry Profile and submit an Expression of Interest. You will be ranked based on your skills, language, work experience and other factors. Through Express entry regular draws, candidates with top scores are invited to apply for the permanent residency.
If you have job offer you need not register with the Canada Job Bank. In case if you have job offer then, you need not register with the Job bank. The chances of getting PR for candidates with Job offers is very high.
Express Entry is a permanent residence program for skilled professionals. It is the skilled economic immigration program. You will have benefits of all the social welfare schemes of Federal Canada with the permanent resident ship.
There are three classes under which you have to opt a category.
Federal Skilled workers program-- For software professionals, Managerial posts.
Federal Skilled Trades Program - For skilled and semi skilled workers in service industry and different for workers within different trade categories.
Canadian Experience Class --- Skilled workers with Canada experience of one year.
In case if your willing to apply for any particular province of Canada, you can opt that province as your priority through Provincial Nominee Programs.
This fast track system is flexible, your express Entry profile will remain active for an year.