Plaster has been applied for many centuries and in the earliest of times, was applied to a solid surface like a pyramid wall. But there is historical evidence that early man, using mud as a form of plaster, applied it to a framework of sticks and interwoven reeds. This stick and reeds was the first form of what we use today in our plaster environment, that binding framework known as lath.
Our modern forms of exterior lath are an intricate, sometimes artful, form of various configurations of metal. Some are welded into an engineered web, others stamped and expanded to create hexagonal shapes and yet others woven into octagonal nets, all designed to carry the weight of the cement cladding, stucco. Lath performs other functions as well. Yes it primarily holds the weight of the stucco cladding, maintaining the vertical plane, fighting gravity, but lath also works to gauge the thickness of the stucco. To some of us believers, the lath also acts as a sort of spandex for the building, keeping the framework from bulging and twisting all the while maintaining its sleek architectural form.