A shirt is a kind of cloth which is made to cover the chest and upper body. In North America, types of shirts include T-shirts, polo shirts, etc. In Britain, a shirt has a garment with a collar, sleeves with cuffs and a full vertical opening with buttons. (North Americans would call this a "dress shirt", a specific type of "collared shirt"). Some shirts have sleeves, which cover the arms. T-shirts are a type of shirt which has shorter sleeves. These sleeves cover the shoulders. Shirts which do not have sleeves are sleeveless.
The basic measurements are from XXXL (very large) to XXS (very small) used during industrial productions. More accurate measurements use the collar, which has indication from 37 cm (14 in) up to 50 cm. Only shirts made by tailors (people who make clothes as a living) take many measurements into account for a shirt that fits the best.
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Shirt Facts for Kids. Kiddle Encyclopedia.