In the context of the nRF Connect for VS Code extension and the nRF Connect SDK, boards are target systems with a defined set of embedded devices and capabilities, which can load and execute an application image, as per Zephyr's board definition. A board can contain one or more Systems-on-Chip (SoCs).
Each board can have one or more board targets, which are descriptions of a hardware design that can be provided to any of the Zephyr build tools to compile and link an image for a particular hardware system. In some cases, the board target name can be synonymous with the name of the board. See Zephyr's Board terminology for more information.
The extension allows you to work with boards that are supported by the nRF Connect SDK and to add your own boards.
You can choose a board target for your application when you are adding or editing a build configuration.