Admission is free.

1 p.m.: "Reckoning Past and Present"

Guided tour of the collection of calculating machines and of the exhibition of geometric constructivist art in the Arithmeum

2:30 p.m.: "A Walk through the Heart of a Computer"

Everyone has something to do with computers, in everyday life or at work or during leisure hours. But no one really knows the answer to the question: how does it work, in other words, how does it do its calculations? Because all a computer can do is to calculate! We will take you on an entertaining, easy-to-understand walk on which you will meet transistors , the logical AND, OR, and INVERTER, and you will see how a FULL ADDER, an important chip component, is realized on a chip.

4 p.m.: "Presentation of the Z 25"

Public demonstration of a fully functional Zuse Z 25 built in 1968, and introduction to ALGOL programming by mathematicians of the Research Institute for Discrete Mathematics