Do I call for a national insurance number to work surrounded by the UK?

I just received my working holiday visa for the UK. Its only virtuous for two years and I wanted to know if I need a national insurance number over near to work or do I just show any potential employer my work holiday visa? I would think I would entail a number in order for both the employer and me to payment taxes?
Answers:
It would seem so...the information you require is here...
http://www.dwp.gov.uk/lifeevent/benefits…
If you want to work here legally, yes.


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