Its also known as a tesseract, A hypercube is a multidimensional analogue of a 3-dimensional cube in that each coordinate of a point in a hypercube is restricted to the same 1-dimensional (line) segment. The Tesseract is a 4-dimensional hypercube. In simple terms, its a box of wonders...
Practical uses for hypercubes or tesseracts is all mathematical theory for now.
But, imagine if you where to build one: Think of a small shoebox and fill it with the entire contents of your house! Ya can even set it up to fill it with all your Neighborhoods entire household goods! The plus side, you can lift the box and dont feel any weight at all and transport your entire neighborhood somewhere else!
Negative side, How do you keep it stable from collapsing onto itselfe and how to power it into existance. My friends theorised its not necessary to use brute power to bring it to existance, but find the right harmonics to make it and keep it stable.