Which nail condition is characterized by ridges on the nail surface?

Onychorrhexis is indeed characterized by ridges on the nail surface, which can present as longitudinal grooves or splits along the nail. This condition is typically a result of various factors such as aging, trauma, or underlying health issues, which can weaken the structure of the nails. Ridges may be indicative of a lack of moisture or nutritional deficiencies as well. In a nail technology context, recognizing this condition is important because it can inform proper nail care and treatment approaches, ensuring both aesthetic and health considerations are addressed for clients.

The other options represent different nail conditions: Onychomycosis refers to a fungal infection of the nails, while a hangnail is a small piece of skin that tears near the nail, and psoriasis is a chronic skin condition that can affect the nails by causing pitting or discoloration, but not typically defined by ridges.