1. A skin marker for providing a reference point for a plurality of different medical imaging procedures, said marker comprising: at least one substance having one or more properties chosen from (i) radiance, (ii) hydration, (iii) radiopaqueness, (iv) radio luminescence, and (v) radioactivity, for detection by one or more of (i) X-ray, (ii) Computer Tomography (CT), (iii) MRI, (iv) Ultrasonic scanning processes, and (v) Positron Emission Tomography (PET); at least one first marking comprising a substantially non-reflective marking that is recognisable by MoirÃ© Fringe 3D scanning processes; and at least one second marking comprising a coloured marking recognizable by a colour recognition imaging process; wherein said at least one first marking is distinguishable from said at least one second marking by the MoirÃ© Fringe 3D scanning processes, and wherein said at least one second marking is distinguishable from said at least one first marking by the colour recognition imaging process.