Baker's Yeast (Active Dry, Cake, Inactive Dry, Rapid Rise) - A yeast (Saccharomyces cerevisiae) that is used as a leavening agent. The yeast converts the fermentable sugars in dough into carbon dioxide which causes air bubbles to form in the dough. Red Star sells gluten free yeast products.
Brewer's Yeast (Bottom Fermenting, Top Fermenting) - Brewer's and Winemaker's use different types of yeast to produce their different beverages. The type of yeast used during the fermentation process will impact the final flavor of each beverage.
Nutritional Yeast - A nutritional supplement with a cheese like flavor that is high in various B vitamins. It does not replace other forms of yeast that are used as a leavening agent or in brewing. You can purchase nutritional yeast from Bob's Red Mill.