Geotechnical engineering is a branch of civil engineering that focuses on the behavior of earth materials. It involves studying soil, rock, and groundwater to assess their properties and how they interact with structures. This field is essential for designing foundations, retaining walls, and tunnels, ensuring that these constructions are safe and stable. Professionals in geotechnical engineering, known as geotechnical engineers, use various techniques, including soil sampling and laboratory testing, to gather data. They analyze this information to predict how the ground will respond to loads and environmental changes, helping to prevent issues like landslides or foundation failures.