Jerez has exported wines since at least Roman times, and today its wines account for the greatest volume of any Spanish DO exports. They are sold in fifty countries. One of the beauties of Jerez DO is the versatility of its different types of wines, which are grouped into three general categories depending on the characteristics of the musts and the winemaking and ageing processes that each undergoes: generosos, vinos generosos de licor (sweet generoso wines) and vino dulce natural (sweet natural wines).