Knit fabrics contain loops of fibers that allow the material to stretch in one or both directions, while woven fabrics only stretch on the bias. In knit fabrics, a continuous loop of yarn is used to construct the material, giving it a braided appearance. In woven fabrics, multiple strings of yarn cross each other, creating the appearance of a basket weave.
There are two types of knitted fabrics: weft-knitted and warp-knitted. Weft-knitted fabrics are constructed by looping long strings of yarn together by hand or using a machine. This type of knit is used to make socks and T-shirts. Warp-knitted material is constructed of yarn that interlocks vertically. This type of knit stretches less than weft-knitted material, and it is used to make swimwear and underwear.
Woven fabrics are constructed using yarn in a combination weft and warp weave. In a weft weave, the yarn goes across the width of the fabric, while a warp weave goes down the length of the loom. There are three types of woven fabric: plain-weave fabric, twill-weave fabric and satin-weave fabric. In a plain weave, the warp and weft are aligned, forming a crisscross pattern. A twill weave features a weft and warp pattern that is offset to create a diagonal pattern on the fabric's surface. A satin weave uses a complex arrangement of warp and weft threads to create a smooth, shiny surface.