A hairnet, or sometimes simply a net or caul, is a small, often elasticised, fine net worn over long hair to hold it in place. It is often worn by food service workers to prevent hair from contaminating the food. A snood is similar but a looser fit and with a much coarser mesh.

Evidence has been found of hairnets as far back as ancient Greece,^{[dead link]} further evidence are known from archaeological finds of Iron Age bog bodies from Denmark and Germany. Hairnets were worn from the 13th century onwards in Germany and England and are shown in illustrations from this period often worn with a wimple. They were made from extremely fine silk and edged with bands of either finger-weaving or tablet-weaving.

Ena Sharples, a character in the UK soap opera Coronation Street between 1960 and 1980, was famous for wearing a hairnet.

Hairnets are part of normal attire for female horse riders and are worn in most equestrian disciplines, including dressage, eventing, show jumping and hunting. Organisations such as the Pony Club encourage their young members to become accustomed to wearing hairnets when around horses, not only to ensure a neat and elegant appearance, but also to eliminate any danger of scalping should the rider fall off and the horse tread on loose hair.

Oprah Winfrey (born Orpah Gail Winfrey; January 29, 1954) is an American media proprietor, talk show host, actress, producer, and philanthropist. Winfrey is best known for her self-titled, multi-award-winning talk show, which has become the highest-rated program of its kind in history and was nationally syndicated from 1986 to 2011. She has been ranked the richest African-American of the 20th century, the greatest black philanthropist in American history, and was for a time the world's only black billionaire. She is also, according to some assessments, the most influential woman in the world.

Winfrey was born into poverty in rural Mississippi to a teenage single mother and later raised in an inner-city Milwaukee neighborhood. She experienced considerable hardship during her childhood, claiming to be raped at age nine and becoming pregnant at 14; her son died in infancy. Sent to live with the man she calls her father, a barber in Tennessee, Winfrey landed a job in radio while still in high school and began co-anchoring the local evening news at the age of 19. Her emotional ad-lib delivery eventually got her transferred to the daytime-talk-show arena, and after boosting a third-rated local Chicago talk show to first place, she launched her own production company and became internationally syndicated.