If you’re a Pages user, you may be somewhat frustrated by some apparent limitations in the way the page-layout application’s ruler works. When you drag a tab stop on the ruler, it moves in full steps between each tick mark on the ruler. But what if you want more precision?
It turns out you can precisely place your tab stops by holding down the Command key before dragging—you’ll have absolute control over their positioning. This also works for positioning the left margin at a precise point.
Speaking of the left margin in Pages, the ruler can also prove frustrating if you’re trying to create a hanging indent—it’s not obvious how to move the tab without also moving the left margin. To do so, hold down the Option key before dragging either the tab stop or the margin marker. However, this won’t give you fine control—both will move one full ruler tick mark at a time. To give fine control over the position of either the tab stop or the left margin, hold down the Command key in addition to the Option key before dragging.
As far as I can tell (via searches on Command and Option in the Pages’ User Manual), these modifier key behaviors aren’t documented.