Glossary
UART
A simple asynchronous serial interface, often left on embedded boards as a boot and debug console.
A Universal Asynchronous Receiver-Transmitter sends data one bit at a time without a shared clock; both sides agree on a baud rate and frame format such as 115200 baud, 8 data bits, no parity, 1 stop bit (8N1). On a circuit board a UART appears as TX, RX and GND lines, typically at 3.3 V or 1.8 V logic levels.
Embedded devices frequently expose a UART console that prints bootloader and kernel messages and may offer a shell. Assessors use a USB-to-UART adapter at the correct voltage to read it; manufacturers should disable or authenticate the console on production units.