This new edition, complete with all the necessary material on a free computer disk, strives yet again to provide readers with a working knowledge of chaos theory and dynamical systems. It does so through parallel introductory explanations in the book and interaction with carefully-selected programs supplied on the accompanying disk. The programs enable readers, especially advanced-undergraduate students in physics, engineering, and math, to tackle relevant physical systems quickly on their PCs, without distraction from algorithmic details. For the third edition of Chaos: A Program Collection for the PC, each of the previous twelve programs is polished and rewritten in C++ (both Windows and Linux versions are included). Each chapter utilizes an easy-to-follow structure, from theoretical background and numerical techniques, through interaction with the program and computer experiments, to real experiments and empirical evidence. It's topped off with a section of references.