It can be challenging to comprehend the idea of the fourth dimension.

We can only see three dimensional aspects of our
environment, but theoretical physicists believe that there may be additional
dimensions that exist outside the range of our perception, among which is the
fourth dimension. In addition to the dimensions that determine length, area,
and volume, this one is a postulated spatial dimension.

We already know that there is no fourth dimension that we
can see or perceive, and although researchers have attempted to explain time
travel through the fourth dimension, their explanation still seems fictitious.
What good is knowing about the existence of the fourth dimension if we cannot
see it or use it to travel back in time? For mathematicians and physicists,
comprehending these higher dimensions is crucial because it aids in their
understanding of the world. For example, string theory cannot function without
at least ten dimensions [source: Groleau]. According to these researchers, the
next dimension—and beyond—may hold the solutions to challenging issues in the
three-dimensional world.

This amazing high school student does an amazing job of
explaining the fourth dimension, even though it's a difficult concept to
understand.