warp v. weft

Image courtesy of Merriam-Webster’s Visual Dictionary. To make woven fabric, threads of a strong yarn are placed in tension on a loom. These lengthwise fibers are called the warp of a fabric. The yarn that runs back and forth across the width of the fabric is called the weft or the woof. The weft is interlaced under and over the parallel warp threads, and because it isn’t placed under high tension, it doesn’t have to be as strong as the warp.

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