When you press a key, watch a video, or call a friend, your device doesn’t understand “A,” “blue,” or “hello.” Deep inside, it only speaks one language: two tiny symbols, 0 and 1. In our last post we met Boolean algebra — the arithmetic of true/false, on/off, 0/1. Now let’s take a journey to see how those two little symbols grew into the foundation of our entire digital universe.

Long before smartphones, early engineers asked: “If a telegraph wire can only be on or off, how can we send numbers?” Humans use the decimal system (ten digits, 0–9). Machines needed a base that matched their physical reality. Two states meant base-2, or binary.