Oral leukoplakia is the most common oral potentially malignant disorder and presents predominantly as a white lesion of the oral mucosa. Although relatively uncommon, its prevalence is estimated to be less than 1% of the population. Both males and females are affected with similar frequency. The condition is rarely observed during the first two decades of life and occurs more frequently among tobacco users than non-users. Leukoplakia can develop at any site within the oral cavity and is often asymptomatic. Diagnosis is primarily based on careful clinical examination, including visual inspection and palpation, as no adjunctive diagnostic aids have proven sufficiently reliable for establishing a definitive clinical diagnosis. The evaluation of pigmented lesions affecting the oral cavity and perioral tissues remains a diagnostic challenge due to the wide range of possible aetiologies. While epidemiological factors and characteristic clinical features may assist in narrowing the differential diagnosis, histopathological examination is often required to establish a definitive diagnosis. Oral pigmentation may be physiological or pathological in origin and may result from endogenous or exogenous factors. Important diagnostic considerations include the lesion's colour, location, distribution, duration, associated systemic conditions, medication history, family history, and any recent changes in appearance. Darkly pigmented oral lesions may present as focal, multifocal, or diffuse macules and encompass a variety of entities, including physiologic racial pigmentation, melanotic macules, melanocytic nevi, blue nevi, smoker’s melanosis, oral melanoacanthoma, foreign-body pigmentation, drug-induced pigmentation, Peutz–Jeghers syndrome, Addison’s disease, and oral melanoma