Waste refers to any unwanted, discarded, rejected, or abandoned material, substance, or object that is generated as a result of human activities and is no longer considered useful by the person or organization producing it. Waste may exist in solid, liquid, or gaseous form and can arise from domestic activities, agriculture, industries, healthcare facilities, commercial establishments, construction activities, and many other sources. Some wastes are relatively harmless, whereas others may be infectious, toxic, corrosive, flammable, radioactive, or otherwise hazardous to human health and the environment. The nature of waste therefore depends greatly on its source, composition, quantity, and method of disposal. From the perspective of environmental health, improper waste management can contaminate air, water and soil and can provide breeding places for disease vectors such as flies, mosquitoes and rodents. Healthcare waste is particularly important because it may contain infectious materials, sharps, pathological waste, chemicals, pharmaceuticals and other hazardous substances. Safe management requires segregation, collection, storage, transportation, treatment and disposal according to applicable regulations. In India, healthcare waste management is primarily governed by the Bio-Medical Waste Management Rules, 2016 and subsequent amendments. Waste can be classified in several ways, including according to its physical state, composition, hazard potential and source of generation. Classification according to source is especially useful because the source generally determines the characteristics of waste and the appropriate method of management. Municipal or domestic waste is generated from households and residential communities. It includes food scraps, vegetable and fruit residues, paper, cardboard, plastics, glass, metals, textiles, packaging materials, ash and other discarded household articles. Kitchen and garden waste usually constitute the biodegradable fraction, while plastics, metals and glass are largely non-biodegradable. Household waste may also contain potentially hazardous materials such as batteries, paints, cleaning chemicals, electronic waste and discarded medicines. If municipal waste is not properly collected and disposed of, it can cause foul odour, attract insects and rodents, clog drains and contaminate surface and groundwater. Commercial waste originates from shops, markets, restaurants, hotels, offices, banks and other commercial establishments. It commonly consists of packaging materials, paper, cardboard, plastics, food waste, discarded products and other materials associated with business activities. Restaurants and hotels generate substantial quantities of organic food waste, whereas offices generate large amounts of paper and packaging waste. Markets may produce considerable quantities of biodegradable vegetable and fruit waste. Segregation at source and recycling can significantly reduce the quantity requiring final disposal. Institutional waste is generated by schools, colleges, universities, government offices, research institutions, prisons and other organizations. Much of this waste resembles municipal waste and includes paper, stationery, food waste, packaging materials, plastics and garden waste. However, educational and