Have you ever wondered what things in the universe is made up of? Atoms, protons, neutrons or things smaller than them? The answer is elementary particles. This book is a short journey to the world of these particles. This book takes the reader step-by-step through atom, nucleus and then, to the world of particles such as protons and neutrons, and finally, to the elementary particles. The nature and behaviour of the elementary particles are explained using Feynman diagrams in light of Standard Model of Particle Physics. Thus, this book serves as a brief introduction to particle physics explained in simple language.