So I was at work a couple months ago, and it was a place where uniforms are issued to most of the employees. Some new people were getting theirs that day, so there was some discussion about clothes. The topic of washing and care came up, and I was surprised to find that none of the people there (all men, as it happens) knew much about fabrics. They didn't know, for instance, that pea coats are made of felt, which is in turn made of wool. They also didn't know what rayon and polyester were made out of. Without Googling, can you tell me what polyester is made out of? How about rayon?