A plug is a device used to connect electrical equipment to a power source or outlet. It typically consists of two or three prongs that fit into corresponding slots in an outlet. Plugs are designed to ensure a secure and safe electrical connection, allowing the flow of electricity from the power source to the device. Different types of plugs and outlets exist around the world due to variations in electrical standards and voltages. Adapters may be used to convert plugs for use in different regions.