Shellac is a specific brand name from the CND company, and manicures bearing the Shellac name use a special formula called Power Polish, which blends ultraviolet light and regular nail polish. A Shellac manicure is essentially the same as all other gel manicures.
Like other types of gel manicures, the Shellac version relies on UV light to treat the nails and give the treatment its durability; these varnishes can last up to two weeks. The Shellac manicure produces a less sticky paint; it appears thinner.
People can remove their Shellac treatment by purchasing special wraps from Shellac's manufacturer, CND. These are acetone-based products.