The growing population and industrialization have made it necessary to invent new technologies that can use rice husk, a type of lignocellulosic biomass, for waste disposal and cost reduction in industries. Rice husk (RH) is a renewable agricultural waste material that is available in abundance in Cambodia, Brazil, China, Myanmar, India, USA, and other South Asian rice-producing countries. Although millions of tons of rice husk are produced globally every year, it has been utilized for its recycling mainly for small value-added usage only in the recent past. Over the years, several countries with rice production’s rice mills have begun to utilize RH for energy making for power plants and domestic lighting in rural areas. Rice husk has been burnt to produce rice husk ash (RHA). Disposal of RHA in landfills or open grounds is not advisable and has implications that are environmentally and health-wise hazardous because of its low bulk density. To overcome this problem, different approaches for the commercial application of RHA are being considered. Silica, which constitutes 83–90% of RHA, is amorphous in nature and has numerous uses. Current and potential applications and research on RHA include using RHA in producing activated carbon, silica gel, silicon chips, and silica. RHA is also being considered for application in the manufacture of lightweight construction material and insulation, catalysts, zeolites, components of lithium-ion batteries, graphene, energy storage capacitors, carbon capture, and drug delivery systems. RH with high silica content can be transformed into biofuels including bio-oil, steam, and biochar through pyrolysis and gasification processes.