What was a Token Ring network?

Token Ring was an IBM-backed networking technology announced in 1985 that competed with Ethernet in the 1980s and 1990s but ultimately became obsolete. While Token Ring was more robust than early Ethernet—eliminating collision problems by passing a "token" around the network—it lost market dominance primarily because Ethernet was significantly cheaper (about a third of the cost) and scaled to higher speeds more quickly. Token Ring's main vulnerabilities were its high cost and requirement that all devices on the network operate at the same speed, making it incompatible with mixed-speed systems.