In more recent years, many monasteries and abbeys in Europe, and especially in Belgium, have used their brewing talents as a way to pay for the day-to-day expenses of living in meditation and praise to God.
This leads me to the first lesson of Belgian beer label interpretation: A beer that is labeled as an abbey beer or refers to an operating abbey in its name can be brewed by any large or small brewery. There is no legal requirement that such a beer be affiliated with an actual abbey (though some are) and may even assume a fictitious name for marketing purposes. This may seem a bit shady, but many of these beers are very well crafted. It's just a Belgian thing.
Abbey beers vary in style and strength but typically follow a very simple designation of blond, amber or brown. Some designate beers as dubbel and tripel, originally based on a taxable strength designation. This has become more of a style designator with dubbel being dark and malty, and tripel being light in color but strong and spicy. Complex malt flavor is the goal here along with some complex esters and phenolics produced by specific Belgian yeast strains during fermentation. I recommend beers by St. Feuillien and St. Bernardus in this category.
Trappist beers are brewed specifically by monastery breweries operated by the Trappist order. Of the seven operating Trappist breweries, six are in Belgium. The word "Trappist" cannot appear on the label or in the description of a beer unless it is actually brewed under control of the Trappist order. Authentic Trappist beers bear the Trappist shield trademark.
Another feature denoting some Trappist beers is a raised ring around the neck of the bottle. The only non-Trappist brewer to ever gain a license to use such trade dress is New Belgium Brewing, based in Fort Collins, Colo. Brooklyn Brewing Co. was asked to stop its use of a double ring on some of its Belgian-style bottles.
The majority of Trappist brewers follow a similar range of styles to their abbey counterparts with each having something a little different to stand out from the crowd. Chimay denotes its style range by label color (red, white and blue), while Abbey Rochefort uses a progressive numbering system (6, 8 and 10) to denote relative strength and complexity.
Orval (brewed by Abbey Notre Dame D'Orval) is the most unique in both packaging and flavor. Orval is available in one style (gold cap) and size (33 centiliters). The beer is about 6 percent abv and is akin to hoppy English ale that has been slightly soured by brettanomyces yeast, making the beer highly carbonated, dry, extremely frothy and delicious as it pours from a unique bowling pin-shaped bottle. It's one of my favorite beers.
Orval is readily available in Charleston along with Trappist brands Rochefort, Chimay and Westmalle. I also recommend Westmalle's dubbel and tripel and also Rochefort's 10.
For more on the craft of beer, see Rich Ireland's "Beers to You" blog at thegazz.com.