It was quite the revelation for me when I discovered that cotton is a terrible material to put on your feet. I've been wearing wool socks every day for years now (even in very hot weather) and my feet have never been drier or more healthy.
+1
https://en.wikipedia.org/wiki/Wool
In addition to
clothing, wool has been used for blankets, horse rugs, saddle cloths, carpeting,
felt,
wool insulation (also see links) and upholstery. Wool felt covers piano hammers, and it is used to absorb odors and noise in heavy machinery and stereo speakers. Ancient Greeks lined their
helmets with felt, and Roman legionnaires used breastplates made of wool felt.
Wool has also been traditionally used to cover
cloth diapers.[
citation needed] Wool fiber exteriors are hydrophobic (repel water) and the interior of the wool fiber is
hygroscopic (attracts water); this makes a wool garment suitable cover for a wet diaper by inhibiting wicking, so outer garments remain dry. Wool felted and treated with
lanolin is water resistant, air permeable, and slightly antibacterial, so it resists the buildup of odor. Some modern cloth diapers use felted wool fabric for covers, and there are several modern commercial
knitting patterns for wool diaper covers.
Initial studies of woolen underwear have found it prevented heat and sweat rashes because it more readily absorbs the moisture than other fibers.