Adobe InDesign question

[iAsuno]

does the page size mean the size of the cover and other pages (pages, yes i know, just making sure) or does it mean the paper that will be used ( for example i put letter size, does that mean letter sized paper that will be folded into 2?)

[smokincola]

Paper size is controlled by your printer, what InDesign and Photoshop do is target an optimized state for a certain paper size. I think it's generally assumed you're targeting print (as in getting some printed properly at a professional printers, CMYK and all that) so the page size is an optimization for the target print size. However at the print settings dialogue there are of course options for scaling the image thus reducing the quality (printing an A3 picture on an A4 printer etc etc etc).