JPEG is commonly used method of lossy compression for digital photography (image). The degree of compression can be adjusted, allowing a selectable tradeoff between storage size and image quality. .jpg or .jpeg is the most common image format by digital camera and on website.

PNG is a raster graphics file format that supports lossless data compression. PNG supports palette-based images, grayscale images and full-color non-palette-based RGB[A] images. .png format is often used for transferring images on the Internet.

JPEG format can produce a smaller file than PNG for photographic, since JPEG uses a lossy encoding method.
When storing images that contain text, line art, or graphics, the PNG format can compress image data more than JPEG can.
Early web browsers did not support PNG images.
JPEG does not support transparency.

Other Comparison: 3GP vs 3G2 / MP4 vs FLV / MKV vs MP4 / MP4 vs MP3 / 3GP vs MOV / 3GP vs FLV / M2TS vs MP4 / MP4 vs 3GP

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