What are the differences between HTML5 and (pre-5) HTML? How can I make HTML-like forms in Markdown? What is difference between Hypertext and Markup in HTML?
You set the inches and the number of pixels in each of those inches. Photoshop removes or adds data to fit the number of pixels in each of the inches you specified. Note: The original image used in the examples below is 4x4 inches, 100 ppi, 400x400 pixels at 468.8 KB.
I always design them in Photoshop using CMYK color. As was said before, I always add a little to the width height to allow for bleed. I think the standard size for inserts is 4.5 x 4.5, same for the actual CD itself. But I'm not sure if that's exact.