Muslin is a type of finely-woven cotton fabric, introduced to Europe from the Middle East in the 17th century. It was named for the city where it was first made, Mosul in what is now Iraq.

Muslin is typically a closely woven unbleached or white cloth, produced from corded cotton yarn. "Sheeting" is the name for wide muslin. It is often used to make dresses and curtains. In clothing, muslin breathes well, and is a good choice for hot, dry climates.

The word "muslin" is also used colloquially. In the United Kingdom, many sheer cotton fabrics are called muslin, while in the United States, muslin sometimes refers to a firm cloth for everyday use. In British slang, muslin may refer to women or femininity, while in nautical slang, muslin can refer to a vessel's sails.

Muslin is often times used proficiently in a theatrical setting. It is helpful in masking the background of sets and helping to establish the mood of different scenes. It can be painted to look like countless different settings and if it is treated properly it can become translucent. With the right lighting changes, a backdrop painted on muslin can appear or vanish, allowing a set to be transformed almost instantaneously from one setting to another.

Muslin can also be used as a cheap greenscreen, either precolored or you can paint it with cheap latex paint (diluted with water).