What are logarithms? Why do we need logarithms? They undo exponentials. They're inverse functions. Part 1: logarithms are defined, and a number examples of moving between logarithm form and exponential form are shown. The common log (base 10) and natural log (base e) is explained, followed by the change of base formula. Part 2: How to evaluate logs (logarithms) without a calculator by changing it into exponential form, and examples of why logarithms and exponential functions being inverses helps in simplifying expressions. Part 3: Beginning with a review of exponential graphs, logarithms are explored as inverses (everything that was x becomes y and everything that was y becomes x). Horizontal asymptotes are now vertical asymptotes and y-intercepts are now x-intercepts. This is followed by transforming those basic graphs.