Compression of Photos online

[Mergingtraffic]

When you post photos online such as Flickr, FB or even on this forum etc....does the act of posting them compress the photos? I notice the quality isn't as great when I look at them online compared to when I look at my original files on my hard drive.

[hbelkins]

Facebook compresses them, unless you select the "high quality" option when you upload -- and even then, there is likely some image degradation.

Flickr, I think, stores images at the original resolution but offers a number of options if you share an image off their site.