First thing's first: ginger beer was the very beginning. It originated in the 1800's in England and, at that time, did contain a small percentage of alcohol. Around 100 years later, the ginger ale we've come to know and love was developed and came to be known as Canada Dry. The difference? Ginger beer is actually brewed and fermented while ginger ale is essentially a carbonated beverage made from water and ginger. Ginger beer often has much more of a "gingery" flavor and because it's fermented, is less carbonated. My favorite brands are the unfiltered ginger beers like Seattle's fantastic Rachel's Ginger Beer - it is slightly cloudy and has an unprecedented ginger flavor. I've started to buy ginger beer at the store now instead of ginger ale because the latter often has so much more sugar and often isn't even made with real ginger.
Related: Try This! Easy Homemade Ginger Ale
(Image: Emma Christensen)