Wastewater refers to the liquid waste that is generated by various sources, including domestic residences, commercial properties, industries, and agricultural activities. This type of wastewater typically contains a mixture of water and other materials, such as food particles, oils, chemicals, and human waste.

Wastewater is typically discharged into a sewer system or treatment plant, where it undergoes a series of processes designed to remove contaminants and make it safe for discharge into the environment. However, the presence of contaminants in wastewater can pose a significant threat to human health and the environment if not properly treated.

Sources of wastewater may vary depending on the location and nature of the activity. For instance, in urban areas, domestic wastewater may be the primary source of wastewater, while in agricultural areas, the wastewater generated may contain pesticides and fertilizers.

In summary, wastewater is a complex mixture of liquid waste that requires proper management to protect public health and the environment.