Checklists are used in many fields like healthcare and aviation to prevent errors and ensure important steps are not skipped. The presenter started using checklists after reading "The Checklist Manifesto" which describes how checklists have saved lives. Good checklists are precise, efficient, and to the point without trying to spell out every step. They remind users of critical steps. Checklists have their limits but can help experts remember complex processes and prompt better functioning. The presenter provides examples of checklists they have created and used for usability testing and collaboration meetings.