What is Public Relations?

I first remember coming across the term "PR" several years ago when watching neighbours. I remember that Flick wanted to do PR at uni and was despairing because her UAI wasn't high enough. Instead she was offered a job in "Public Relations" which involved her parading around corporate parties wearing barely any clothes, serving drinks to clients. I think the idea was to provide an appealing impression for possible clients. She was told by her boss that she didn't need a degree to become a PR officer, all she needed was the right attitude. At the time I thought that parading around half-naked wasn't a very positive attitude to have, and this is one of the most common misconceptions about Public Relations - that all the job entails is parties and cocktails. Chapter 1 of Public Relations, Theory and Practice, clarified my understanding of PR as an occupation. Far from parties and cocktails, PR is a lot of hard work to provide a postive image and reputation for a company, organisation or person.
I especially appreciate Don Barnes' four points of public relations practioners' functions as being:
1. to advise management on policy and its effect on public relations;
2. to channel and coordinate within an orgainisation the activities that affect public relations;
3. to provide the mechanics for explaining an organisation and its policies to its various publics through communications media;
4. to ascertain and explain to management what various publics think about the organisation.