Refers to software that has been specifically compiled for a particular processor. For example, the Pentium can run software designed for the x86 architecture faster than existing x86 computers like the 486; however, the software must be recompiled to take full advantage of the Pentium's superscalar architecture.
Software written specifically to run on a particular processor. Also, the file format in which an application normally saves it documents. The native format is generally readable only by that application (other programs can sometimes translate it using filters). [San Diego State University
Not counting, or prior to applying, any of: scaling, upconversion, downconversion, encoding, decodiing, modulation, demodulation, etc. For example the native resolution of "720p HDTV" is 720 pixels high by 1280 pixels wide but a particular TV set with a native 4:3 aspect ratio resolution of 640 by 480 on an LCD panel can convert a 720p 16:9 program to fit by displaying half the program's resolution horizontally and vertically, 640 by 360.