What the heck is beer anyways?

Over the past few weeks I have had quite a few very similar discussions with several different people. Sometimes it's occurred over the consumption of a couple of cold ones, and once it happened in the context of creating a couple cold ones.

The discussion has been based around the question: 'What is beer and how's it different from ale?' Now, full disclaimer I am by no means an expert and after these discussions I have done a cursory search of the all-mighty interwebz, which has neither confirmed or denied what I have said in the discussions.

Photo from:
http://www.outsidethebeltway.com/wp-content/uploads/2012/04/toast-beer.jpg

Now you might be wondering why is this important and what if I don't drink beer. Well this is important because what other fun facts are you going to throw around while drinking beers with friends? That a fully grown male grizzly can run up to 35 MPH and swim up to 15MPH (I don't know how many knots that is) or that giraffes sometimes eat bones to maintain their freakishly large skeletal structure, no that's just silly. And if you don't drink, well surely you will at some point meet someone that does or even better is drinking a beer and in that situation you can teach them a little something about what they're ingesting and pat yourself on the back for bustin' out some fun facts.

So, based on my limited research and the conversations that I have had...

Beer is a fermented beverage where the sugars are provided by a grain or cereal base; hops, fruits and other nice tasting things are often added to make it more palatable.

Ale is often times a beer brewed with a specific strain of yeast, an ale yeast which does best in warmer temperatures and can have a higher alcohol tolerance than other yeast strains.

The tricky bit that has led to discussions is: 'What about ginger ales like this one?' You may notice that there are no grains present in the recipe but the suggested yeast is indeed an ale yeast. So, I argue that the aforementioned ginger ale is not a beer but it is indeed an ale because of the yeast strain.

A root beer, in the traditional sense, is NOT a beer though because it is neither fermented, nor does it have a grain base. Similarly, ginger ale that you get at the supermarket, I argue is not really ginger ale but a ginger soda or ginger drink, anything but an ale/beer.

What do you guys think? Any other caveats that you can think of or anything you disagree with?

Additional resources (sources from my quick googling):

http://www.wisegeek.org/what-is-the-difference-between-beer-and-ale.htm#didyouknowout

http://bendbrewfest.com/beers.htm
l - This one kind of confirms my argument