OK, Ale is basically fermented at warmer temperatures, using a "top fermenting" yeast. The fermentation happens roughly between 64 and 75°F, some different yeast strains are happier at different points in the range.
Lager is a bottome fermenting yeast, and requires colder temperatures - usually some modest refrigeration is required to keep it happy. These also tend to ferment longer and result in a "cleaner" flavour, that is to say less flowery if you like. It's all open to interpretation really, flavour wise.
There are also variations between ales and lagers in terms of ingredients, but only in subtelties. Lagers are brewed from one type of barley malt, ales from others. Some lagers also use malt made from wheat (then again so do some ales).
At the end of the day, both ale and lager start from 4 key ingredients, malt, hops, water and yeast. There are many varieties of all 4 ingredients - including the water, so the range of beer possibilities is endless. :cheers:
That SA brew is indeed pretty good. for more info on brewing check out
www.northernbrewer.com - they are a home brew supply shop, with a good website. Even if you don't want to brew your own, there is some good info there, written a lot better than I can put it.