Small Caps vs. All Small Caps

The OpenType controls in QuarkXPress have two options for Small Caps: “Small Caps” and “All Small Caps”. (These options are available only in fonts that contain true small caps glyphs — otherwise these options have brackets around their name in the menu.) 

The difference between them is that Small Caps makes only the lowercase letters into small capital letters, while All Small Caps replaces every letter with the small cap glyphs.