It's basically someone who decides what will be sold at stores, and this is from a two minute Google search.
I think you posted this yesterday or something, and seeing the views but no replies... I think it's a pretty small career. I know it involves going to buy the clothes for the stores, but it's got to be a VERY difficult field to get into. If you make it to the top, you'll probably be fine. But that could take time and a lot of effort. In the mean time, you'd probably have to work someplace that doesn't provide much.....so you have to take all of these things into account.
I assume you are talking about a personal buyer, and not a buyer for the store. And that Is all I know about those fields.