We live in a four-dimensional universe defined by three spatial dimensions and one time dimension. In other words, it only takes three numbers to pinpoint your physical location at any given moment. On Earth, these coordinates break down to longitude, latitude and altitude representing the dimensions of length, width and height (or depth).

In our everyday world, we often use three dimensions: height (up and down), width (left and right) and depth (forward and backward) to describe the location of objects. These three dimensions create what's called 3D space.

The spatial dimensions—width, height, and depth—are the easiest to visualize. A horizontal line exists in one dimension because it has only length; a square is two-dimensional because it has length and width. Add depth and we get a cube, a three-dimensional shape. These three coordinates are used to pinpoint an object’s location in space.

In geometry, a three dimensional shape can be defined as a solid figure or an object or shape that has three dimensions— length, width, and height. Unlike two dimensional shapes, three-dimensional shapes have height, which is the same as thickness or depth.

Shapes that can be measured in 3 directions are called three-dimensional shapes. These shapes are also called solids. Length, width, and height (or depth or thickness) are the three measurements of three-dimensional shapes.