Denim is made from tightly woven fabric that usually comes from cotton warp yarn and white cotton filling yarn. The filling yarns are stretched across the width of the fabric and interlaced at 90-degree angles with warp yarns, which are also stretched the length of the fabric. This creates an interwoven pattern of diagonal lines called “twill weave.” There are two kinds of twill weaves: left hand twill, which is softer and runs diagonally from right to left, and right hand twill, which runs diagonally from left to right and is flatter and smoother.
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