And now, for something completely different... I saved the screenshot below with my graphics editor, "Paint.Net", whose default save format is .png. Then I realized I should save it as a .jpg to get reduced file size, and did so. To my surprise, the lossy .jpg turned out to be considerably larger (7x bigger) than the lossless .png.
Odd.
It's not really so odd. Different formats for different purposes. JPG was created for use on photographs, which typically have lots of high-frequency data (leaves in trees, sensor noise, etc), and gradual transitions between objects (blurs, etc). PNG was a replacement for GIF images, which were typically graphics (as in graphic design) characterized by high contrast/sharp color transitions, and very little high-frequency data. And don't forget that "lossless" isn't the same as "uncompressed."
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