در مورد شخم تعاریف مختلفی ارائه شده است، ولی یكی از ساده ترین آنها تعریف زیر است. عمل زیر و رو کردن خاک به منظور اصلاح ویژگی های فیزیکی آن می گویند.
Plowing goals are realized when it is done at the right time and under the right conditions. One of the most important conditions for the successful implementation of plowing is that the soil moisture is good or favorable at the time of plowing. Based on this, if soil moisture is less than optimal for plowing, it should be irrigated first.
Plowing is one of the most important soil management practices, used for centuries to create a straight, grained, structural, and moist sowing layer. Plowing is a simple, but effective farm practice that cuts, granulates, and inverts the soil, creating furrows and ridges. Depending on the depth and time of plowing there a few types of plowing, including:
tillage, in agriculture, the preparation of soil for planting and the cultivation of soil after planting. Tillage is the manipulation of the soil into a desired condition by mechanical means; tools are employed to achieve some desired effect (such as pulverization, cutting, or movement). Soil is tilled to change its structure, to kill weeds, and to manage crop residues.