Plow
A plow is an agricultural implement used to turn the soil prior to sowing it with seeds. plows are traditionally drawn by draft animals (oxen or horses), which serve to lift a large burden from the human population. The invention of the plow is an absolute necessity for anyone endeavoring to rebuild society, as the plow has likely freed up more human labor than any other invention in human history.
Without a plow, it is necessary to either agitate the soil manually using a hoe, or to turn the soil manually using a shovel, depending on the exact nature of the soil to be tilled. Very light, fertile soils, such as the alluvial soils which once characterized Egypt and Mesopotamia can be tilled using merely a hoe. However, heavier and less fertile soils universally require the soil to be turned for crops to be able to establish themselves.
Although the aforementioned areas in the world with light, fertile soil may be able to make use of an ard for tillage, a rudimentary plow which merely agitates the soil like a hoe, rather than turning it like a shovel, most soils will require the use a moldboard plow. A moldboard plow slices and flips the soil as it is moved, rather than merely agitating it.
The Moldboard Plow
In most regions, a moldboard plow will provide better, more effective tillage than an ard would. A moldboard plow is composed of two major components, the plowshare and the moldboard. The plowshare is a sharp implement at the front of the plow whose purpose is to cut through sod and weeds. The moldboard is the section which flips the slices which the plowshare makes. A coulter may also be present, which is a sharp blade affixed in front of the plowshare to further help cut through the soil. The rest of the plow consists merely of structural components which serve to hold it together and allow it to be drawn by the draft animals.