Definition
5G is the fifth generation of mobile network technology, standardized by 3GPP from Release 15 onward, targeting higher data rates, lower latency, and far greater connection density than 4G.
How it works
5G introduces a new radio interface (5G NR) and a service-based core network, with mechanisms such as network slicing and edge computing. It deploys in low bands for coverage and in high bands such as mmWave for capacity, in either non-standalone (NSA) or standalone (SA) modes.
Usage
Beyond faster mobile broadband, 5G targets factory automation, vehicle networking, and massive IoT deployments that need low latency or huge connection counts. Operators can slice the network so different services receive different guarantees.
Related and confusable terms
Wi-Fi is a wireless LAN technology on unlicensed spectrum — complementary to cellular 5G, not a competitor. An eSIM is the form of identity module a device uses to authenticate to a cellular network such as 5G; the two operate at different layers.