A projector resolution when the unit is able to project an image greater than its native resolution.
A method of reducing data from a higher resolution to enable images to be projected by a projector with lower true resolution. Most SVGA (800x600) projectors offer compression capabilities for handling images from XGA (1024x768 pixels) i.e. a higher resolution than their true (or native) resolution.
Anytime a projector can accept a higher resolution signal and compress the data down to fit its true resolution. Quality of compressed images varies tremendously. Most but not all projectors offer compressed resolution for handling higher res then their true resolution. Some use simple "line dropping" schemes while others achieve varying degrees of higher quality with different "intelligent" algorithms.