Species Interactions is a clear, engaging introduction to how life holds together. Written for readers with no prior background, it reveals the everyday logic behind the living world—how species compete for resources, how predators and prey shape each other, and how microbes, plants, and animals form partnerships that make survival possible. This book moves from core concepts like niches, food webs, and trophic dynamics to practical views of symbiosis, microbial ecosystems, network stability, and resilience. Along the way, it shows how observation, simple experiments, and pattern recognition can turn any backyard, park, or city block into a living classroom. The result is a friendly yet rigorous guide to seeing, understanding, and caring for the connections that sustain ecosystems and our daily lives.