In this episode Shahriar investigates the impact of linearity and distortion on analog circuits. The source of a non-linear input/output characteristic is presented in three different domains: mathematical, time domain and frequency domain. After the theoretical discussion, a sample circuit is built and tested to illustrate real time signal distortion. The criteria for measuring non-linearity is also presented. Furthermore, the importance of a two-tone test for bandwidth limited circuits is shown theoretically and experimentally. There is another quiz in this episode! Please discuss the answer on the forum or in the comment section.