The image shows a diagram of three cubes nested within each other, representing a tesseract (a four-dimensional hypercube). Each cube is labeled with a number (6, 5, and 4) and has its faces colored with different hues. The colors include red, orange, yellow, green, blue, purple, pink, ochre, and white. The innermost cube (labeled 4) is a solid brown. The middle cube (labeled 5) has a light brown interior. The outermost cube (labeled 6) has a brown interior. The diagram is accompanied by text that explains it represents the tesseract, red, yellow, blue axes in space, with the blue axis running to the left, and opposite faces are colored identically.