Verified answer

I think the fourth is actually a combination of time and space known as "spacetime"... this is according to Einstein at least.

And no, no one can explain dimensions beyond the fourth because humans do not have the mental capacities to think about an experience that we, well, cannot possibly experience with any of our senses.

Actually, its more like this:

(think of an Excel worksheet)

1. One dimensional is a list where each point occupies one cell in the list from top to bottom. One point per row

2. Two dimensional is where a point can occupy a cell in the same row different column as anther point,

3. Third dimensional is where a point can occupy the same row and the same column as another but on a different sheet.

In other words :

one dimensional has length, two dimensional has lenth and width, and three dimensional has length, width and height.

The forth dimensiional means two point can share the same length, width, and height at a different time.

A building, you can go to room at x row, y column, on z floor and so can I. The only thng separating us is Time.

These are the only dimensions we can experience, the others are beyond us.

It isn't that simple but we know they exist. Why? Theoretical physics like super string theory needs them or else you get these infinities that make nonsense of the fabric of reality.

We know they must exist because of places like black holes. Imagine a place so dense that light does not escape. Where time itself doesn't exist. Where the laws of nature are gone. Which has a surface which cannot be described.