different JPG compressionsJPG – the omnipresent standard for images in digital photography, very efficient in file size, disregarded by some because of concerns with regard to image quality.

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What is JPG (or JPEG)? »
How does JPG work? »

The possible loss of image quality with sample pictures:
Best possible JPG quality »
Loss of quality 1: Color shift »
Loss of quality 2: Artifacts »
Loss of quality 3: Square shaped blocks and loss of details »

JPG-compression and file size »
Summary and recommendations for the JPG format »