I am hoping someone can help me to develop a working definition for the term "dimension". In the past I was taught that there is the first dimension which is a single point, the second dimension is defined as this single point being extended in such a way that a second dimensional object would consist of a point that extends into a line which ends in a right angle and that right angle ends in a right angle and that right angle ends in a right angle until the fully defined second dimensional shape is a plane, the third dimension continues working with this concept so that every end point of the plane extends into a right angle so that the plane becomes a cube. Going with this concept a fourth dimensional object I have heard called the name tesseract. The tesseract being a third dimensional object which is extended into right angles at every end point like the two dimensions before it. My confusion is as follows: I know "time" is often called THE FOURTH DIMENSION. Is this because one working definition for a dimension is a way to define a position? For example: "A" exists at x, y, z coordinates WHEN -- and then a time is given without which the location could fall short of indicating position (unless object "A" somehow exists from the beginning of time for all eternity, that is the only exception I can think of where time is not required to pinpoint location...but even then perhaps. .. . Part of my confusion in understanding how the term dimension is defined is a result of what I have heard about string theory in which it is suggested that if string theory has any validity it requires 32 dimensions. Are these dimensions an extension of the tesseract, going with the idea that each higher dimension is generated by extending the previous dimensions corners into right angles to itself? But then if this is so, how does time come under the definition of a fourth dimension? If string theory requires 32 dimensions, and having 32 dimensions is something considered, than even if the fourth dimension is time, how does one define the fifth dimension?