What is a polo shirt?

A polo shirt is a form of shirt with a collar, a placket neckline with typically two or three buttons, and an optional pocket. It is usually made of knitted cotton (often pique knit) or, less commonly, silk, merino wool, or synthetic fibers. Polo shirts are often short-sleeved; they can also be long-sleeved. They are usually more casual than dress shirts, but smarter than a T-shirt. They are a popular choice for both men and women.