A regional lockout (or region coding) is a class of digital rights management preventing the use of a certain product or service, such as multimedia or a hardware device, outside a certain region or territory. A regional lockout may be enforced through physical means, through technological means such as detecting the user's IP address or using an identifying code, or through unintentional means introduced by devices only supporting certain regional technologies (such as video formats, i.e., NTSC and PAL).