What is public opinion? What does public opinion do with you? Does public opinion have a temper? The author joined hands with "public opinion" for more than two decades, and integrated many years of observation experience into the hotspots of public opinion, and wrote "How much is a catty for" false public opinion "," Who sacrificed for public opinion "," You liar "," Wu Hezhong ", etc. Twenty notes, using smooth texts to tell people: Public opinion is everywhere, no one can hide. These twenty notes are both academic and readable, and strive to be targeted and systematic. They will comment on public opinion events, popular science phenomena, analyze public opinion strategies, and discuss public opinion safety in as easy-to-understand manner as possible. These 20 notes, from shallow to deep, from the surface to the inside, can be ordinary readers to understand the phenomenon of public opinion, can also be used by public opinion workers to take stock of public opinion work, or experts and scholars to discuss the safety of public information.