M2M penetration, the number of machine-to-machine (M2M) SIM cards on mobile networks per 100 inhabitants, provides a measure of one component of the Internet of Things (IoT) - for which machine-to-machine communication is an important foundational technology. The indicator relates to SIM cards assigned for use in machines and devices (e.g. cars, smart meters, consumer electronics) and that are not part of a consumer subscription. These SIM cards can be embedded in machines such as personal navigation devices, smart meters, trains and automobiles, among many other applications. Dongles for mobile data and tablet subscriptions are excluded.