Penetration of water into a medium, for instance the soil. The process of infiltration measures the rate at which the soil on the ground absorbs rainwater or irrigation water. Some of the metrics that are taken into account are the millimeters and inches per hour. It works by the infiltration rate as the soil grows in saturation. Infiltration occurs when the water is absorbed into the soil within the ground and moves throughout the soil and sediments. The plants benefit from some of this water distribution and help to release the water into the air through the spores on their leaves.