Multi-up printing is the process of shrinking more than 1-page of your original print job onto each sheet of paper that weill be printed by iPrint (to your real printer).

For example, you can ask iPrint to place 2-pages on each sheet of paper... this saves you 50% straight away and even more importantly, it makes a lot of printing much more readable because it's in a more familiar book-format - with pages side by side.