A piezometer is a simple device used to measure the pressure of liquids, typically groundwater. It consists of a tube that is open at the bottom and filled with liquid, often water. When the tube is inserted into the ground, the height of the liquid column indicates the pressure exerted by the surrounding water. This measurement helps in understanding groundwater levels and flow. Piezometers are commonly used in fields like civil engineering and hydrology. They can provide valuable data for projects involving dams, wells, and landfills, helping engineers assess soil stability and water management strategies.