What is the difference between one dimension two dimensions and three dimensions?

Answer 1

It's a difference in how things are perceived. For instance, our world is three-dimensional. Imagine looking at one side of a piece of paper. That's one dimension. Now look at both sides of the paper; front and back, it's two dimensions. Now imagine the paper turns into a box. That's three dimensions.

1-length

2-width

3-height

That answer is just so wrong.

A line is one dimensional. It has just length no width or height. (This is an ideal line, not one that you draw since that WILL have a width - it will be as wide as your pencil point.)

A sheet of paper is two dimensional (NOT 1-d as stated above). The other side of the sheet of paper is completely irrelevant. A sheet has length and width. If you hold it up, it has length and height (or width and height). Again, this is an ideal sheet of paper, since it will have a very very tiny width (or thickness).

Finally, a cube (or a box), which has length, breadth and width is three dimensional.