In the 21st century, nanotechnology has experienced significant growth, thanks to its numerous applications in the field of quantum physics. It has become a highly advanced field of study, with significant efforts focused on researching to apply this technology in practical ways. It shows great potential due to its impressive effectiveness and environmentally friendly characteristics. Nanomaterials are incredibly tiny particles, measuring between 1 and 100 nanometers. Their size grants them unique chemical and physical characteristics, which come with advantages and disadvantages. Their classification can also be done on their composition such as organic, inorganic, and metal. Various techniques are employed to synthesise nanomaterials, including both the "top-down" approach, which starts with bulk materials and breaks them down into nanoparticles, and the "bottom-up" approach, which begins with individual atoms and builds them up into nanoparticles. Among the top-down approaches are “mechanical milling”, “nanolithography”, “laser ablation”, “sputtering”, and “thermal evaporation” while the bottom-up approaches are “sol-gel”, “biosynthesis”, “spinning”, “chemical vapour deposition (CVD)”, and “pyrolysis”. These techniques are highly influenced by factors such as temperature, pressure, time, size and shape, preparation cost, pore size, pH value, and environment. This study examines different methods of synthesizing nanomaterials along with their applications in different fields such as cosmetics, electronics, medicine, food, and the environment.