For centuries framed walls had been covered by three layers of plaster laid over thousands of lath boards nailed end to end over a wood frame. Anyone who has a home built before 1940 has probably seen the results of this process from the inside when remodeling or repairing. The first layer of plaster was pushed between the lath boards (which were about 2 inch strips) and made a large unified surface. The next coat of plaster was put on to begin the smoothing process and then a final coat was made to create a smooth wall. This was a laborious and time-consuming process.
Wallboard had originally been invented in 1916 by the United States Gypsum Company. It was basically gypsum squeezed between two panels of paper. It could be quickly nailed onto a frame and the seams between sheets could be plastered to make a seamless wall. However, wallboard failed to catch on, in spite of being used extensively at the Chicago World's Fair in 1934.
World War II, the genesis of so much innovation, would prove to be the catalyst that would drive the use of gypsum wallboard. For the first time since the Civil War there was a shortage of manpower. The old methods of plaster and lath were simply too cumbersome and manpower intensive. The U.S. Government and various industries seemed to simultaneously discover the U.S. Gypsum Company and their amazing product, which they called "drywall" (because it went up dry rather than having to go on in wet plaster layers that took so much time to dry).
In the drywall system there was only a need for a thin coat of plaster. The labor costs were a fraction of those for lath and plaster. Thousands of new buildings were made using drywall. As efficient as Drywall (also called Sheetrock) was, it made a cheaper, hollow sound when knocked upon. For this reason many thought it was going to be a temporary replacement for the old system. Nevertheless, its cheapness proved to be a huge advantage in building homes and other structures at less expense, making them available to more people. The square lines, more uniform, level surfaces proved to be attractive and flexible.
Today, drywall, Sheetrock, wallboard, whatever you choose to call it is found in most buildings and homes. Seldom is the old method of lath and plaster even attempted except for historical renovation.