The Optoma HD25 supports a maximum resolution of 1920 x 1200 (WUXGA). That's over seven times the resolution of a 640 x 480 (VGA) projector, which is the most common resolution supported by projectors that have been available for a comparable time to the HD25. 640 x 480 (VGA) is also supported by this data projector. In addition, this Optoma projector support graphics resolutions of 1024 x 768 (XGA), 1280 x 1024 (SXGA), 1280 x 768 (WXGA), 1280 x 800 (WXGA), 1360 x 768 (WXGA), 1400 x 1050 (SXGA+), 1440 x 900 (WXGA+) and 1600 x 1200 (UXGA) and 800 x 600 (SVGA).
This projector's resolution (1920 x 1200 (WUXGA)) is actually the best supported resolution amongst all similar spec multimedia projectors that are a comparable age to the HD25.
The worst supported resolution across similar types of projector is 640 x 480 (VGA).