Sometimes used during the pre-visualization phase of complex projects, 3D virtual tours and panoramic videos are used primarily for validation. =Considerably more lightweight and compact than full HD video, these 3D renderings are best suited for emails correspondence and sharing. Clients sometimes use 3d virtual tour files for their websites. Although HD videos offer superior quality, they are linear while 3D virtual tours and interactive panoramas are non-linear allowing the client to control where they want to view.