This self-contained work on linear and metric structures focuses on studying continuity and its applications to finite- and infinite-dimensional spaces. It motivates the study of linear and metric structures with examples, observations, exercises, and numerous beautiful illustrations. It also includes applications to geometry and differential equations, historical notes and a comprehensive index. The book may be used in the classroom setting or for self-study by advanced undergraduate and graduate students and as a valuable reference for researchers in mathematics, physics, and engineering. This book builds upon the discussion in the authors’ previously published books to provide the reader with a strong foundation in modern-day analysis.