Which condition is characterized by dark spots or patches on the skin?

Hyperpigmentation is a condition where specific areas of the skin become darker than the surrounding skin. This darkening occurs due to an excess production of melanin, the pigment responsible for skin color. It can manifest as dark spots or patches, often resulting from factors such as sun exposure, hormonal changes, inflammation, or skin injuries.

In contrast, vitiligo is characterized by the loss of skin pigment in patches, leading to lighter areas rather than darker ones. Psoriasis is a chronic skin condition that causes red, scaly patches, often with silvery scales, and is related to the overproduction of skin cells rather than pigment changes. Rosacea primarily presents as redness, visible blood vessels, and sometimes acne-like bumps, but does not cause dark spots or patches.

Understanding these distinctions helps in identifying and diagnosing skin conditions accurately, focusing on the specific characteristics of hyperpigmentation, which is the hallmark of the correct response.