The specific hardware variant of ST-Link we'll be using in our exercises isn't actually made by SEGGER. It is the ST-Link circuitry already included on the Nucleo development board. Nucleo boards have two separate sub-circuits: programming hardware and target hardware. 

The programming hardware sub-circuit is generally referred to as an ST-Link. This programming hardware is actually another STM MCU that is responsible for communicating with the PC and programming the target hardware—the STM32F767. Since Nucleo hardware is primarily aimed at the ARM Mbed ecosystem, the ST-Link MCU is programmed with firmware that implements both the ST-Link and Mbed functionalities:

In order to use the programming hardware on the Nucleo board as a SEGGER JLink, we will be replacing its firmware with SEGGER J-Link on-board firmware.