The typical kilt as seen at modern Highland games events is made of twill woven worsted wool. The twill weave used for kilts is a 2-2 type, meaning that each weft thread passes over and under two warp threads at a time.

The result is a distinctive diagonal weave pattern in the fabric which is called the twill line. This kind of twill, when woven according to a given color pattern, or sett , is called tartan. In contrast, the Irish kilt traditionally was made from solid color cloth, with saffron or green being the most widely used colours.