If you work only with basic word processing or text documents, then the Print dialog in Mac OS X is really simple: just tell it which pages to print, how many copies you want and which printer to print from. Easy. And maybe also tell it to scale the pages to fit the paper. Still easy.
But if you work with a complex desktop publishing application such as Adobe InDesign or QuarkXPress, there are dozens of choices based on what you've created, the kind of printer you're using, and the process that will be used to produce your final printed product. Here's a down-and-dirty overview of what you need to know, and what you can ignore, in InDesign's Print dialog.
Adobe has done an admirable job of not only grouping the printing options into logical panels, but making those options context-sensitive. Thus, they change according to the printer you've chosen. So, if you choose a desktop inkjet printer, your options will be different than those available for a PostScript laser printer or imagesetter.
The General panel is fairly self explanatory, you're telling InDesign which parts of your document you want to print. If your document is designed like a magazine, with left and right pages, the Pages section lets you print them side-by-side on the same sheet of paper but you may need to scale the pages to fit on the paper. If you've used InDesign’s Master Pages to structure your document pages, you can print those pages from here as well.
The Options section lets you override any object-specific or layer-specific printing or visibility settings you've made on the pages, and forces all the objects or layers to print. This also where you can force InDesign to print any blank pages in your document (normally InDesign saves paper by ignoring blank pages) and to print the page grids and guides you've used. Printing the guides can help a colleague understand a document’s page structure when you hand off a project to them.
The Setup panel is also pretty obvious, you can scale a page to fit the paper in your printer, control where a smaller page will print on the paper (centred is often helpful), print multiple tiny thumbnails of your pages on each sheet, or break up a larger page so that it prints on multiple smaller sheets that you can tape together (called tiling). The Preview window at the bottom left is tremendously helpful for seeing when you've made a terrible mistake such as setting a vertical page to print horizontally.