what is a public prosecutor?

In a criminal trial, it is the state/government vs. the accused. So the state is represented by the prosecutor. For example if it is a murder trial it will be the state vs. the accused murderer. The prosecutor works for the city/state (the government) and will be pressing charges against the accused murderer in court. Other terms for a prosecutor that you may hear are DA (district attorney) and city attorney. I hope that makes sense.

Giselle, to give you a better idea of what I was doing when I was in practice, I was an associate at 2 different law firms after graduating and passing the bar. I represented insurance companies in Workers' Compensation cases. Employers in the US must have Worker's Comp insurance and when an injured worker/employee gets hurt at work and files a claim, the employer advises the insurance company and the insurance company will obtain an attorney to litigate the claim. Often times the insurance company will pay the injured worker in a settlement (more often than not) and the objective is for the employee to get medical treatment and resume work. In a nutshell I appeared at administrative hearings (much less formal than what you see on TV), depositions (in an office setting, you question a witness and a court reporter records it), and I drafted many legal documents. I did quite a bit of research as Workers' Comp defense is an ever-changing field of law. When I became in-house counsel at Berkshire Hathaway I started out doing the same type of work but before I resigned I was doing case management and working with the insurance claims people (they are the ones that the employer speaks with after an employee files a claim, like the person you talk to when you have a car accident and call the insurance company) as a liaison between the legal department and the claims department. I really liked my job and I would likely still be there if I wasn't a mother. Hope that helps!