GoKawiilUSB-A and USB-C explained: how the two connectors differ
USB-A is the original rectangular USB connector from the USB 1 standard, designed with a one-way host-to-device connection so it only fits one way and can't be flipped freely. USB-C is the newer, smaller, reversible connector that replaced older peripheral formats like USB-B, Mini-USB and Micro-USB, especially on modern mobile devices.