The second most abundant crop in the world is rice which produces 20–33% rice husk (RH), as biomass of approximately 139.54–230.24 million tons. Its open combustion discharges harmful organic contaminants like polycyclic aromatic hydrocarbons and dioxins along with injurious gases such as CO2, CO, SO2 and NOx. The presence of residual carbon and silica in rice husk ashes (RHAs) may lead to the accumulation of ash in riverbeds, affect soil pH, and alter the general characteristics of the soil and water. It is not a good source of feedstock due to low nutrients, lignin, ash contents and high silica. It constitutes about 20% of the husk and 4% of the total weight of the rice paddy. The rice husk is primarily composed of phosphorus (P), potassium (K), residual carbon (C), and silicon (in the form of silica—SiO2). The trace elements found are sodium (Na), calcium (Ca), magnesium (Mg), iron (Fe), copper (Cu), manganese (Mn), and zinc (Zn). Cellulose, and lignin, account for 50%, and 30% and the remaining 20% is made up of organic compounds but the inorganic part is mostly composed of amorphous hydrated silica. The husk is processed into three types based on their main component: silicon-based, carbon-based, and hybrid which consist of silicon as well as carbon. Reactive hot-pressing is an economical technique used in the production of advanced ceramic materials such as silicon carbide (SiC), silicon nitride (Si3N4), and even very pure metallic silicon. Rice husk pure and modified biochar have been utilized for the adsorption of contaminants such as heavy metals, other cations, dyes and tetracycline. The nutrient-loaded rice husk biochar improved the soil fertility and cation exchange capacity. RH is used as fuel in small power plants due to its high caloric value (16.7 × 106 J kg−1). Furthermore, the conversion of RH not only has a detrimental effect but also generates methane and hydrogen, which may serve as alternative energy sources. Moreover, it is used in civil engineering which acts as a filler and adhesive in construction materials. Furthermore, it functions as a replacement for strengthening agents in polymers, as well as in glass and refractory materials and also in the production of zeolites.