Wool is one of most versatile fibers. It is such a complex blend of properties that modern science still cannot duplicate it or create a synthetic clone. Textiles created from wool range from thick and coarse carpets to extremely fine merino underwear suitable for a baby's skin. Because they live in extreme climates, sheep have managed to evolve a highly sophisticated covering for themselves. Their fleece, with its tightly crimped fibers, contains many air pockets that insulate them, and us, from the cold.

            In scientific terms, the outer cells of the fiber repel water while the inner cells absorb moisture, which is the property that makes wool such a warm material. Wool is highly absorbent, capable of retaining up to 25% of its weight in moisture. It becomes warmer to the wearer as it slowly absorbs moisture from the air. Also wool is slow to feel damp, and it dries as slowly, and so does not chill the wearer by drying too fast as cotton and silk can.

Wool is naturally flame-retardant, owing to its tendency to retain moisture. Also its absorbency makes wool ideal for dyes-wool takes on richer, deeper, purer colors than vegetable fibers can. Today, the main areas of wool production are Australia, New Zealand, South Africa and Argentina.