Understanding 3 Dimensions is one and only way to get in the world of 3D. Let’s try to understand what the dimensions are? When we draw something on paper like sheet or surface, we use 2 dimensions.
A photograph is two dimensional thing, a shadow is a two dimensional entity as well. A 2 dimensional object is always drawn on 2 dimensional surfaces like paper, and has two axes for drawing, X, Y, one for length measurement and one for width measurement. But a 3 dimensional object has depth in addition and cannot be drawn on 2 dimensional surfaces like paper. Because a 3 dimensional object is a thing of realistic world like cup, glass, room, fan, computer, ball, book, human, pen, pillar etc. when we model a 3 dimensional object in Maya.
We model it in an imaginary work space, which gives us the illusion of realistic 3D world. We have length, width, depth at a time. We model 3 dimensional objects on 3 axes X, Y and Z.