Before Feller published his first volume in , probability was often treated as a messy collection of "tricks" for games of chance. William "Vilim" Feller, a Croatian-American mathematician, set out to change that by treating it as a self-contained, rigorous mathematical subject.

Feller’s work is famous for blending high-level theory with vivid, real-world examples:

He didn't just want to solve math problems; he wanted to show that probability governed the . Key Chapters in the "Story" of Probability