Graphic Designer:
Qualified to develop and produce artistic images and layouts based on artistic integrity and technical skill.

Sales Representative:
Their job is to sell space or time in their newspaper, radio station, or television network. They can offer advice on where to place your ads.

Advertising:
Advertising is just one aspect of "marketing". Advertising is about choosing where, when and how much. The content of the ad is linked to...

Marketing:
This is about developing a clever multi-layered communication that represents you on various fronts. It involves reaching your market by understanding it and tapping into it on a psychological basis.

The process...
A marketing person would develop a plan. They would then have a graphic designer create imagery according to those guidelines. This would then be blended into advertisements in a way that works in with the marketing plan. The advertising people would make certain contributions and then take over the best way to budget and place the ads for maximum effect.