Book excerpt: Recognizing abnormalities and pathologic conditions -- Red and white lesions -- Masses within the soft tissues of oral mucosa -- Oral mucosal, facial, and neck masses -- Infectious diseases of the jaws and oral cavity -- Radiolucent lesions -- Radiopaque and mixed radiolucent-radiopaque lesions -- Radiopaque lesions in soft tissue -- Pigmented lesions of mucosa and facial skin -- Lesions of the facial skin and oral mucosa -- Exposed bone pathologies -- Vascular lesions of oral mucosa and skin