A Native Resolution is a measurement of the number of pixels (or dots) capable of being displayed by your projector or digital display. The most common measurements for projectors are
The WXGA, WUXGA, and UHD resolutions are widescreen with an aspect ratio of 16:10 or 16:9, these are now the standard resolutions in the industry and what are recommended for all uses. The SVGA and XGA resolutions are slowly being phased out. These resolutions create and image in the 4:3 ratio, relatively square in shape. The WXGA resolution is recommended for basic uses such as an average PowerPoint presentation, however for and presentations or displays that require more detail it is recommended to use a 1920x1080 or a 1920x1200 resolution (or higher).
For home theatre there are now 2 main resolutions in use, FULL HD and 4K. FULL HD is perfectly fine for the vast majority of use however 4K is becoming more popular with the increase in 4K movie streaming and 4K channels on PayTV services.