A vinyl decal is an adhesive-backed vinyl design, often more artistic and permanent than a sticker, that can be used for branding, decoration, or functional purposes on various surfaces. Key aspects include the use of different vinyl types for durability and application, with specialized types for permanent or removable uses on walls, vehicles, and windows. The lifespan of a vinyl decal depends on the vinyl’s quality and lamination, with some lasting several years, and application requires proper surface preparation with cleaning agents like isopropyl alcohol to ensure good adhesion.