Two protocol technologies exist that telecoms use when connecting IoT devices to their networks: LTE-M and NarrowBand IoT (NB-IoT). These protocols are low-power, low-cost, low-bandwidth, and specifically developed to connect IoT devices to cellular networks.
NB-IoT is used more often in Europe and is mainly devoted to low-cost and low-bandwidth data connections.
LTE-M is more frequently used in North America, developed with a focus on mobile connections and (comparatively) higher bandwidths.