All of us have a notion of dimensions. We measure the number of kilometers we jog, give appropriate price to a piece of land, and are recommended to drink at least 8 glasses of water a day. In talking about these things, we talk about dimensions. In determining the number of kilometers we jog, we measure length. The price of land is based on its area and other factors. In counting the number of glasses of liquid we drink, we are talking about volume. Length, area, and volume are examples of measurements in 1, 2, and 3 dimensions.
In mathematics, a dimension (of a space or object) is the least number of coordinates needed to specify a point within it. For example, on the number line, which is 1 dimension, we only need one number to determine a point. The number 5 corresponds to the point that is 5 units to the right hand side of 0. » Read more