Drip irrigation is a type of micro-irrigation system that applies water directly to plant roots. The key components of a drip irrigation system include a water source, pumping system, distribution pipes, drip tape with emitters, injectors, and a filtration system. Drip irrigation conserves water by reducing evaporation and runoff, allows for targeted fertilizer application, and improves crop yields. It has been widely adopted for agriculture in water-scarce regions like India and Israel.