Author Clifton Fadiman said it best when he described cheese as "milk's leap toward immortality. " Almost everyone loves one type of cheese or another, whether it's delectably mild, creamy and soft or pungent, hard and crumbly. To begin with, cheese can be broken down into two very broad categories — fresh and ripened. Within these basic categories, however, are a multitude of subdivisions, usually classified according to the texture of the cheese and how it was made. Naturally, many of these categories overlap because a cheese can have an entirely different character when young than it does when aged. Most cheese begins as milk (usually cow's, goat's or sheep's) that is allowed to thicken (sometimes with the addition of rennin or special bacteria) until it separates into a liquid (whey) and semisolids (curd). The whey is drained off and the curds are either allowed to drain or pressed into different shapes, depending on the variety. At this stage it is called fresh (or unripened) cheese. Among the most popular fresh cheeses on the market today are cottage cheese, cream cheese, pot cheese and ricotta. In order to become a ripened (or aged) cheese, the drained curds are cured by a variety of processes including being subjected to heat, bacteria, soaking and so on. The curds are also sometimes flavored with salt, spices or herbs and some, like many cheddars, are colored with a natural dye. After curing, natural cheese begins a ripening process during which it's stored, usually uncovered, at a controlled temperature and humidity until the desired texture and character is obtained. It can be covered with wax or other protective coating before or after this ripening process. Ripened cheeses are further classified according to texture. Hard cheeses are cooked, pressed and aged for long periods (usually at least 2 years) until hard and dry, and are generally used for grating. Among the more well known of this genre are parmesan and pecorino. Semifirm cheeses such as cheddar, edam and jarlsberg are firm but not usually crumbly. They have been cooked and pressed but not aged as long as those in the firm-cheese category. Semisoft cheeses are pressed but can be either cooked or uncooked. Their texture is sliceable but soft. Among the more popular semisoft cheeses are gouda, monterey jack and tilsit. Soft-ripened (or surface-ripened) cheeses are neither cooked nor pressed. They are, however, subjected to various bacteria (either by spraying or dipping), which ripens the cheese from the outside in. Such cheeses develop a rind that is either powdery white (as in brie) or golden orange (like pont L'éVêque). The consistency of soft-ripened cheese can range from semisoft to creamy and spreadable. Some cheeses are further categorized by process. Blue-veined cheeses, for example, are inoculated or sprayed with spores of the molds Penicillium roqueforti or penicillium glaucum. Some of these cheeses are punctured with holes to ensure that the mold will penetrate during the aging period. The result of these painstaking efforts are cheeses with veins or pockets of flavorful blue or green mold. Another special-process category is pasta filata ("spun paste"), Italy's famous stretched-curd cheeses. They're made using a special technique whereby the curd is given a hot whey bath, then kneaded and stretched to the desired pliable consistency. Among the pasta filata cheeses are mozzarella, provolone and caciocavallo. Whey cheeses are another special category. Instead of beginning with milk, they're made from the whey drained from the making of other cheeses. The whey is reheated (usually with rennin) until it coagulates. Probably the best known of this cheese type are gjetost and Italian ricotta. There are a variety of reduced-fat and fat-free cheeses on the market today. They're commonly made either partially or completely with nonfat milk, and supplemented with various additives for texture and flavor. Unfortunately, the more the fat is reduced in cheese, the less flavor it has. Not only that, but the less fat there is, the worse cheese does when melted. The texture of such cheese turns rubbery when heated and, in fact, nonfat cheese never really seems to melt, but obstinately remains in its original form. For these reasons, low- and nonfat cheeses are best used in cold preparations like sandwiches. Imitation cheese is just that — a fusion that generally includes tofu, calcium caseinate (a milk protein), rice starch, lecithin and various additives. It's a nondairy, nonfat, noncholesterol and nonflavor food that, for those who like cheese, is better left at the store. Storing cheese: Firm, semifirm and semisoft cheese should be wrapped airtight in a plastic bag and stored in a refrigerator's cheese compartment (or warmest location) for up to several weeks. Such cheeses can be frozen, but will likely undergo a textural change. Fresh and soft-ripened cheeses should be tightly wrapped and stored in the coldest part of the refrigerator, generally for no more than 2 weeks. If mold appears on firm, semifirm or semisoft cheese, simply cut away the offending portion (plus a little extra) and discard. Mold on fresh or soft-ripened cheese, however, signals that it should be thrown out. Firm and semifirm cheeses are easier to grate if they're cold. All cheese tastes better if brought to room temperature before serving. See also appenzeller; asadero; asiago; banon; bellelay; bel paese; bierkäse; blue cheese; bocconcini; bonbel; boursault; boursin; brick cheese; bryndza; Bûcheron; caerphilly; camembert; cantal; casein; chaource; chenna; cheshire; chèvre; colby; crema dania; creole cream cheese; crescenza; danablu; danbo; derby; devonshire cheese; dolcelatte; double-cream cheese; dunlop; elbo; emmentaler; esrom; explorateur; farmer cheese; feta; fondue; fontina; gervais; gjetost; gloucester; gorgonzola; gourmandise; gruviera; gruyere; handkäse; havarti; herkimer; herve; hopfenkäse; kasseri; kuminost; lancashire; leicester; leyden; lieder-kranz; limburger; liptauer; longhorn; manchego; mascarpone; montrachet,neufchâtel; panir; petit suisse; port-salut; processed cheese; pyramide; quark; queso fresco; queso fundido; raclette; reblochon; romano; roquefort; saga blue; saint andré; samsoe; sapsago; sbrinz; scamorze; stilton; stracchino; swiss cheese; taleggio; teleme; tillamook; tybo; vacherin muenster; .