Feta cheese is a rich and creamy soft cheese of Greece, authentically made of whole sheep's milk, although many are now made with goat's milk or a mixture of the two. It has been around for centuries, and hardly a Greek meal does not incorporate feta cheese in some manner. It is so popular in Greece that very little gets exported. In fact, most of the imported feta cheese comes from Italy. Nowadays, many countries produce forms of feta cheese, including Australia, Denmark, Germany, and of course, the United States.
However, modern-day, less robust versions may be made from cow's milk, skimmed milk, or partially-skimmed milk.
Feta cheese is classified as a soft cheese made of 45 to 60 percent fat whole sheep's or goat's milk. The better fetas are aged (but not ripened) 4 to 6 weeks, cured in a salty whey and brine. Known as a pickled cheese, the flavor of feta becomes sharper and saltier with age. It is creamy white in color with small holes, a crumbly texture, and is normally found in square cakes with no rind.
Feta is prized in salads or eaten as a snack and has the added benefit of melting quickly in hot dishes such as in filling for or stifado.
Unfortunately, due to the great demand for feta cheese in Greece and restrictions on unpasteurized milk, you will probably have difficulty finding the real thing outside of Greece. If you do find it, it will be pricey. Most of us will have to suffer using an inferior but still serviceable imitation.