A septic system is a type of on-site sewage treatment system commonly used in rural areas where centralized sewage systems are not available. It consists of a septic tank that collects and treats wastewater from homes. The tank allows solids to settle at the bottom, while lighter materials float to the top, forming a scum layer. After treatment in the tank, the liquid effluent flows into a drain field, where it is further filtered through soil. This process helps to naturally break down harmful bacteria and nutrients, ensuring that the treated water is safely absorbed into the ground.