Konrad Zuse was a German pioneer in computing, best known for building the Z3 in 1941—the world's first functional programmable digital computer. Later in his career, he explored profound philosophical and theoretical ideas about the nature of the universe. Rechnender Raum (literally "Computing Space" or "Calculating Space") is the title of his groundbreaking 1969 book (published in the series Schriften zur Datenverarbeitung). In it, Zuse proposed that the entire universe operates as a vast discrete computational process, akin to a giant cellular automaton. He argued that physical laws and reality itself emerge from digital, step-by-step computations on a grid of discrete "cells" in space, rather than from continuous analog processes as traditionally assumed in physics. This idea challenged the prevailing view of continuous physical laws and laid the foundation for what we now call digital physics, pancomputationalism, or the simulation hypothesis (the notion that reality might be a computation, possibly running on some underlying "computer"). Zuse's work is widely regarded as the first formal proposal of digital physics, predating similar ideas by others like Edward Fredkin or Stephen Wolfram.