The Universal Serial Bus (USB) is an industry standard that defines the cables, connectors, and communication protocols for connection, communication, and power supply between computers and a vast range of peripheral devices. It was developed in the 1990s to standardize the connection of peripherals and replace the multitude of different serial and parallel ports that were common at the time. USB's key features are its ease of use ("plug and play," where devices are often automatically recognized and configured by the operating system), its ability to supply power to devices, and its tiered speed structure.
It has gone through several major revisions, each offering significantly faster data transfer rates: USB 1.x, USB 2.0 (with its 480 Mbps "High Speed" mode), USB 3.x (with "SuperSpeed" modes reaching 5, 10, or 20 Gbps), and now USB4. In the test and measurement industry, USB has become a very common interface for connecting programmable power supplies and other instruments to a control PC. It offers a simple, single-cable connection that is fast enough for most control and data acquisition tasks. To enable communication, USB relies on "classes," which are standardized protocols for different types of devices (e.g., mass storage, human interface devices).
For test instruments, the key classes are USBCDC and USBTMC.
USB Implementers Forum (https://www.usb.org/)