Holography

Overview
Holography (/ho.lo.gɹɑ.ɸi/ form the greek όλος (holos) meaning whole and γραφικός (graphikos) meaning graphic) is the field of contorting electromagnetic radiation to create images, or solid surfaces, in 3D space called holograms.

Forms
The catch all term for holographic projections is hologram, though often this is used souly to refer to softlight projections with hardlight being refered to by its more specific name.

Softlight
Softlight is intangible and usually used to when projecting images or nonphysical shapes.

Hardlight
Hardlight projections are used to create physical objects.