The term “carbon quantum dots” refers to a surface passivation process used to carbon nanoparticles. These cutting-edge luminescent nanomaterials hold immense promise in numerous domains including catalysis, drug delivery, bioimaging, biosensing, energy conservation, and storage. Their minute size, outstanding water solubility, minimal toxicity, customizable light-emitting properties, and remarkable biocompatibility collectively make them highly advantageous. The production of carbon dots can be achieved through top-down or bottom-up methods. Top-down techniques involve cutting macroscale materials into carbon nanoparticles, with graphene sheets, carbon nanotubes, and even candle soot being used as precursors. This paper briefly discusses some of the preparation methods for carbon dots.