Since the earliest humans to populate the earth, we have gradually tried to understand and control the world around us. In trying to understand various phenomena, humans began to make predictions, for example, about the motions of the planets, eclipses, cycles of rainfall, or the periodicity of certain diseases. However, in the last few decades, the complexity of the predictions needed to be carried out has reached the limits of human ability. Luckily, the dawn of electronic computers has increased our abilities to predict nature, although the problems we are facing now are far more complex than the problems we faced a century ago.Artificial intelligence (AI) machines demonstrate advanced cognitive skills in taking decisions, learning, perceiving the environment, predicting certain behavior, and processing written or spoken languages, among other skills. In addition, the ability of certain species to collectively demonstrate "swarm intelligence" has proven to be useful for solving complex problems that otherwise would be difficult to tackle. The collective power of AI and swarm intelligence can help solve difficult and complicated problems in innumerable areas.This book highlights the wide range of applications in swarm intelligence and AI. It is divided into two sections: "Theoretical Background" and "Trends and Applications". It is a useful resource for researchers and students alike.