USB 1.1 is an early revision of the Universal Serial Bus specification that supports low-speed (1.5 Mbps) and full-speed (12 Mbps) data transfer modes. It was designed primarily for low-bandwidth peripherals such as keyboards, mice, joysticks, and basic human interface devices. USB 1.1 introduced key concepts such as device classes, hubs, hot-plugging, and automatic device detection, but offered limited power delivery and insufficient bandwidth for multimedia or storage-heavy workloads.
