How to build a cheap DIY calculator with an Arduino board

Everyone at school on day or until now had or have a calcultor to make calculation. When you thing today, that a small calculator, smartphone and tablet are more powerful than the computers at the beginning. Computers that needed a big room only for themselve

But now as you know everything changed and you can even create your own calculator. This is what a maker called Kale_3d did. He has built a DIY calculator. With this calculator, you can process basics calculation like addition, substraction, multiply and a division.

His calculator's brain is made with a