We are able to experience only the three spatial dimensions and often consider time as the fourth one, even if we can't imagine a fourth coordinate axis perpendicular to the other three.

How we can use our grasp on those first four dimensions to extrapolate to up to ten dimensions is explained in this video:

[youtube=http://www.youtube.com/watch?v=HvgwR9ERCBo&hl=de&fs=1]

If you've still got some brain juice left on a sunday evening, enjoy!

And if your head doesn't spin after watching it, visit the corresponding blog Imagining the Tenth Dimension.