should I have a Contract

A friend ihas been working in her company for 6 years and does not have a contract. Everyone else has one but she never bothered to ask for one as she did not know if it is a good or bad thing to have one. Any tips!

She has a contract -- just not in writing.

The terms of the contract might not be entirely clear, but there must be a pattern evident after 6 years so that she knows what her duties and responsibilities are, and what she gets in terms of pay and other benefits.