as with most InDesign features, zooming can be done in myriad ways. here are just a few.

obviously there’s the magnifying glass tool which you can click on in your tool panel or, if you want to be tricky, hit ‘z’. with the magnifying tool you just click to zoom in by increments or click-drag to select an area to zoom in on. and you hold down the option key if you want to zoom out.

but there’s really no need to change to that tool when you can activate it temporarily by holding down command-space (or command-option-space for the zoom-out tool). unfortunately apple commandeered this shortcut for spotlight (which I believe was just pure bloody-mindedness). but you can change the spotlight shortcut through system preferences (or, indeed, change the InDesign shortcut through edit > keyboard shortcuts).

there’s a whole bunch of other keyboard shortcuts :
• cmnd-+ = zoom in
• cmnd-– = zoom out
• cmnd-0 = fit page
• cmnd-opt-0 = fit spread
• cmnd-opt-shift-0 = fit pasteboard
• cmnd-5 = zoom to 50%
• cmnd-1 = zoom to 100%
• cmnd-2 = zoom to 200%
• cmnd-4 = zoom to 400%

you can also use cmnd-opt-5 to quickly access the magnification dropdown menu : use your up and down arrows to zoom in and out ; or type in the percentage you want.

check out how zooming with these shortcuts differs depending on whether or not you have anything selected.

but that’s not all…
integral to zooming around the page is the hand tool — to drag another area into view when you’re zoomed in. again, there is no reason to change to this tool. in most instances you can temporarily access this tool by holding down the spacebar. the only time this doesn’t work is when the text tool is selected (for obvious reasons). if it is active in a selected text frame then you have to use the option key — if no text frame is selected you have to use option-space (go figure).