Electrical resistivity tomography (ERT) is a geophysical imaging technique used to visualize the subsurface properties of the Earth. It works by injecting electrical currents into the ground through electrodes and measuring the resulting voltage differences. These measurements help determine how easily electricity flows through different materials, revealing variations in soil, rock, and water content. ERT is commonly used in environmental studies, engineering, and resource exploration. By creating a 2D or 3D model of resistivity, researchers can identify features like groundwater aquifers, contaminated sites, or geological formations, aiding in decision-making for construction and environmental management.