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Coating methods include sugar, film, enteric, and compression coating. Sugar coatings create thick, glossy layers but take more processing time and add bulk; film coatings are generally thinner and faster to apply. Enteric films resist gastric conditions and dissolve at higher pH, while modified-release films can use water-insoluble polymers or pore formers to shape drug release. Formulations may contain a polymer, plasticizer, colorant or opacifier, vehicle, and anti-tack agent. Uniform results depend on process conditions such as spray rate, pan speed, temperatures, and tablet-bed moisture, as well as equipment that distributes spray and removes solvent effectively. Recognizing defects such as mottling, roughness, sticking, cracking, and twinning helps connect coating outcomes to formulation and process choices.