An arrangement of media or collage that captures the overall feel of the proposed application. It can be composed of visual and written artifacts, photographs, swatches of color, snippets of historic texts and visual culture artifacts, clips of visual interfaces and precedent interactive applications images. It is a collage of ideas which will inform and guide the development of your project, and is intended to evoke or project a particular style or concept.
a few related links:
20 pro tips for mood boards (Creative Bloq)
How to create a mood board (Canva)(more graphic/web design focused)
mood boards within a conceptual design / prototyping process:
Project Scorpio / Xbox One (Randy Huynh)
Leap Motion VR / 3d User Interfaces
