This book introduces the key concepts of Java programming through the eyes of a small ladybug called Clara. Clara is a fun and extremely obedient insect, whose journey starts with limited skills. Readers learn programming by making Clara move around and manipulate objects in her world. As the book progresses, Clara becomes more intelligent and acquires new skills and (together with readers) learns by tackling some of the world's greatest challenges. The book explains programming concepts through real-world problems such as launching rockets into space, automatically patching potholes, developing a vacuum cleaner robot, simulating projectile motion, dynamically avoiding obstacles, delivering mail, etc. Every chapter of the book starts by presenting a challenge and then continues to explain new programming concepts with the focus on tackling this challenge. Focusing the new material explanation on these challenges helps to remind the readers of how this material is connected with the problems that they may encounter in the real world and makes it easier to relate to. You can explore all programming challenges presented in this book on the Clara's World website. Every programming problem covered in the book has a corresponding link to a problem template (for those readers willing to attempt the problem themselves), the link to the solution of this problem and a video recording of us solving this problem step-by-step. In addition, at the end of each chapter there is a link to fun exercises that readers are recommended to complete.