It usually means that the laptop has a neural processing unit, which is a low-precision matrix multiplier useful for running neural networks.

When advertised by a laptop manufacturer, it usually means whatever Microsoft is currently shipping with Windows, which may run locally using the NPU, or may rely on Microsoft's cloud services. Their brochure page lists "real-time translation, image generation, and intelligent search" as things it can do locally.

Offline Voice typing/Speech to text is cool.