Student response systems, also known as classroom response systems, audience response systems, electronic response systems, and more generally “clickers”, gained popularity in college classrooms starting in the early 2000s. In these systems, instructors would pose a question verbally, by typing it “on the fly” into the software system, or in a pre-planned presentation displayed to students. Students used a physical device to respond to questions, typically in multiple-choice format, with the press of a button. Those responses were recorded by a receiver and summarized by a software system running off a computer workstation. Instructors could immediately display aggregate results, typically in the form of a histogram of the answer choices selected to the entire class to provide immediate feedback to students and/or as a genesis for a discussion on the question. Responses could be collected anonymously or recorded in a database for purposes such as assigning class participation grades and taking attendance.