An activation code is a special string of letters, numbers, or other symbols that is used to register or activate a piece of software or hardware. This code is typically given by the product's creator or manufacturer and is necessary to access all of its features. To ensure that only authorized users can use the product, the activation code serves as a security mechanism. The software or equipment is activated and can be used without limitations after the code has been input. The activation code may occasionally also be used to confirm that a product is legitimate and hasn't been unlawfully copied or pirated.