The document discusses various types of ichthyoses and ichthyosiform syndromes. It describes ichthyosis vulgaris, X-linked ichthyosis, lamellar ichthyosis, epidermolytic hyperkeratosis, harlequin fetus, bullous ichthyosiform erythroderma, ichthyosis linearis circumflexa, Netherton syndrome, Refsum syndrome, KID syndrome, and CHILD syndrome. It also discusses acquired ichthyosis due to vitamin deficiencies, infections, medications, and systemic diseases.