A last is a form, made of wood or more contemporary materials, that is used to shape footwear. Whether you are crafting shoes, boots, or sandals; pattern pieces are cut out, assembled, and stretched over the last. Some materials, such as leather, are first soaked. As it dries, the leather conforms to the the shape of the last beneath it, giving the final product its shape. Most people have both a right and a left foot, the curvature of a shoe ought to match the contours of the foot beneath it so it may come as a surprise to some that the right and left, curved last, shoes are a fairly modern convention. Previously, shoes were straight lasted, right and left were indistinguishable from each other.
Over time, heat and pressure from feet distorted straight lasted shoes, creating a crude customized pair. Modern consumers are used to a consistent barrage of new products, historically markets have been less accepting of change. According to the C & D Jarnigan Company, right and left lastings were available to the United States military as early as 1851, although it purportedly took years before right and left shoes were accepted by the shoe wearing public. Today straight lasted shoes have fallen out of favor. Few companies still manufacture them, although they can be found. Straight lasted shoes may be used to correct certain gaits or address specific foot problems, straight lasted shoes may also be worn by those participating in re-enactments of historical periods as curved lasted shoes would be an anachronism.