This is usually expressed as a dimension. A mesh can be thought of as the domain of the data. It is shown below. The actual values located at the points in the grid. There are two kinds of spaces that describe your data organization, computational space and coordinate space.
Computational space is the parameter space used to calculate or collect the data.
Coordinate and computational space do not have to have the same dimensionality, as some of the examples below will show. Uniform distance between any coordinates along an axis, and is the same for all axes. Points can exist anywhere in space. Consider this example, a pilot flies through a storm cloud collecting water density data at distinct time intervals. She records the density at her current location.