USB's primary function is to establish specifications for connectors, protocols, drivers, controllers, and cables for communication, connection, file transfer, and power supply between computers, computer parts and peripherals, and other computers.
Their driving objective was to develop what would make connecting external devices to computers easier, thereby replacing the multiple connectors that were in use back then.
The device was initially designed to serve as a standard for device connection. Hence, we can safely say the name “Universal Serial Bus” is a descriptor of its specifications.