A scarf is a piece of textile, often long and narrow, usually worn on or near the head, for warmth, fashion, cleanliness, or religious purposes.

In cold climates, a thick knitted scarf (often of wool) is often tied around the neck to keep warm. This is usually accompanied by a warm hat and heavy coat.

The craft of knitting garments such as scarves is an important trade in some countries.

In drier, dustier climates, or in environments where there is a lot of airborne contaminants, a thin scarf is often worn over the head to keep the hair clean. Over time, this custom has evolved into a fashionable item in many cultures, particularly among women.

As well, religions such as Islam promote modest dress among women; many Muslim women wear a headscarf often known as a hijab, but more correctly called the khimar.

Coloured scarves are traditional supporter wear of fans of Australian rules football clubs in the Australian football league.

Students in the United Kingdom traditionally wear academic scarves with distinctive colours which identify their university or college.

In haute couture, the French fashion company, Hermès is famous internationally for its scarves.

Tom Baker's Fourth Doctor on Doctor Who had a 20+ foot long scarf as a characteristic part of his wardrobe.