WHAT'S the best thing to do with inferior wine? For some winemakers the answer is to make it into brandy.

The world's most admired brandies, cognac and armagnac, are made largely from a second rate but productive grape called the Ugni Blanc or St. Emilon. Even in the best of years, Ugni Blanc wines are low in alcohol (about 8 percent) and high in acid: all bite and no bark.

But distill them (in cognac not once, but twice), let them age in oak barrels several years, do a little cosmetic touch up with caramel and voila!, you have $16 worth of liquid lightning standing on the shelf of a local retail shop. Anything that contains enough sugar to turn to alcohol when fermentation is induced can be distiled into spirits. Begin with wine or a mash made from fruit, and you can call the final result brandy. But we'll stick to wine-based brandies. The brandy we have in mind is a golden brown liquid with a pronounced aroma that is an intermingling of grape, alcohol and the wood in which it has been aged (usually oak). It is rather high in alcohol, about 80 proof, and can be harsh in the mouth. The best examples widely available here -- after France -- come from Spain, Greece, Italy, Germany and the United States.

Despite its humble origins, brandy has a distinct snnob appeal. Take, for instance, its highly misleading linkage to Napoleon (who, come to think of it, had pretty humble origins, too). Or all those ads in the posh magazines with brandy snifters as props. Or its price.

I can't do anything about the Price. But we can clear up some misconceptions.

The best place to begin is with cognac and brandy. Cognnac, made in a legally limited area of western France, directly north of Bordeaux, is brandy because of the fashion in which it is made. But no other brandy may be called cognac.

Those letters on cognac bottles are English, not French, because the English were downing great quantities of brandy even before Winston Churchill's time. VSOP means Very Special Old Pale. A bottle with that marking costs more than one marked VS because it has aged longer and, if the additional language fine champagne can be found, because the grapes grew in the high-rent district of Cognac. (Champagne, where the bubbly stuff comes from, is several hundred miles from the champagne areas of Cognac.)

Cognac must be aged at least two years before bottling, but vintage dating has not been allowed for many years and no cognac can claim to be more than five years old. If you see the marking Extra, Napoleon or Vielle Reserve, however, the shipper is telling you it is older than that. Some armagnacs will bear vintage dates. Once in the bottle, brandy does not change its character. Once opened, it will deteriorate. Don't keep an opened bottle of brandy, or store it in a decanter, for more than a few weeks, if that long.

Armagnac is the driest of brandies and can be smoother than cognac. It falls short on finesse, however, lacking that magical sense of rarified grape seeense that emerges from a great cognac. There's a theory that cognac comes into its own only after 25 years in barrel and is at its peak after 40. Some brandy of that age is in the top-of-the-line cognaces that sell for $40 or more a bottle. You are paying, in part, for the extra finesse and the overhead. Not only must the brandy be stored and tended over many years, but the evaporation rate is fearsome. Anyone who tours a barrel warehouse in cognac finds the air rich with one of the world's costlies perfumes.

For all that, consumers often find the lesser grades of cognac harsh and incomplete. You may well decide the brandies of Spain and Greece are more to your taste. They're sweeter and spend less time in wood. In cooking, cognac is best for a last-minute addition to a sauce. But other brandies, including domestic brands, work very well in desserts or for flaming and pouring over various foods.