In two words, "guarantee" and "flexibility." A fixed week will guarantee your accommodations at the resort that you buy for that week and that week only. In most cases, you may exchange your accommodations for another resort, but remember that your "power" may be restricted by which week you own. A Floating Week gives you more flexibility, especially in trading, but no guarantee at any resort including your own. Many resorts have instituted a points based system which allows owners to utilize their ownership for a variety of travel-related products and services such as hotels, airline tickets, car rentals, etc. Be aware, though, that in some cases, points based ownership is NOT ownership at all. The drawback to most points based timeshare is that the point values are not inflation proof. While your week of timeshare may be exchanged for two airline tickets this year, next year that same ownership may only be good for one airline ticket.