Merkel cells are specialized cells found in the skin and some parts of the mucosa of all vertebrates, primarily functioning as mechanoreceptors for light touch. They are located in the basal layer of the epidermis, closely associated with sensory nerve endings, forming what's known as a Merkel cell-neurite complex. These cells are crucial for detecting fine details of touch, including shapes, edges, and textures, and are particularly abundant in areas like fingertips and the oral mucosa.