Ever wondered how vaccines work, why whales strand themselves or if luck exists? The Explainer: From Déjà Vu to Why the Sky Is Blue, and Other Conundrums is a collection of around 100 of the best articles published in ‘The Explainer’ and ‘Monday’s Medical Myths’ sections of The Conversation. The book answers questions on everyone's mind about a diverse range of topics, abstract concepts, and popular and hard core science. Sections include: animals and agriculture, body, climate and energy, medical myths, mind and brain, research and technology, and more. Expert authors combine facts, analysis, new ideas and enthusiasm to make often challenging topics highly readable in just a few short pages. This book is for the curious, those with a thirst for answers, and those with a fascination of how phenomena, new technologies and current issues in our daily lives work.