Born in Canada - live in UK now, am I a Canadian citizen?

[SAbbotts]

I was born in 1975, in Alberta Canada, my parents are both British and had permanent residency at the time of my birth (they emmigrated with a company and got a mortgage and were eligible to apply for citizenship so assuming permanent res.). They did not acquire citizenship before returning to the UK four years later.
I have a Canadian birth certificate. I have a British passport. My mother tried to find out about british and canadian passports when applying for mine when I was 15 but no one seemed to be able to help her and as time was of the essence she just got me a British one.
Am I, by birth, a Canadian citizen?
Can I apply for a Canadian passport too?
If yes, what processing would I have to go through to live and work in Canada.
I now have a small family - would they in turn (assuming I am a citizen) be entitled to apply for citizenship?

[Leon]

You are a natural born Canadian citizen and can apply for a Canadian passport if you want one, see http://www.ppt.gc.ca/cdn/form.aspx?lang=eng&region=international
You can also apply for proof of citizenship for your children, see http://www.cic.gc.ca/english/citizenship/proof.asp

If you are planning on moving to Canada, you can sponsor your spouse for permanent residency, see http://www.cic.gc.ca/english/immigrate/sponsor/spouse.asp and after living in Canada for 3 years, your spouse could apply for citizenship.

[Khilafah5]

ur a canadian citizen by birth