Replying to @Stev How does time fit into the 4D drawing?

This is my 4D drawing of a hypercube, but time is nowhere to be seen. Instead, it's a drawing of a cube in four dimensions of space. Here, we live in three dimensions of space. It is common though to consider time as its own dimension, and in physics, this space-time continuum is called four-dimensional, but time is added on as an extra to the spatial dimensions. In the world of this hypercube then, time could be considered a fifth dimension, and 40 physicists might talk about a five-dimensional space-time continuum. But what's cool is that if you take an ordinary 3D cube and move it over time, you trace out the same thing that I drew. So one way to better imagine what 40 shapes look like is to imagine the path of a moving 3D shape as one solid object. Each snapshot in time would show you one cross-section of that higher-dimensional object. Here, I wrote a whole book about dimensions available at Tibbys.com.