Clicker (classroom)

Audience response is a type of interaction associated with the use of audience response systems, to create interactivity between a presenter and his/her audience. Systems for co-located audiences combine wireless hardware with presentation software, and systems for remote audiences may use telephones or web polls for audiences watching through television or the Internet. Various names are used for this technology, including real time response, the worm, dial testing, and audience response meters. In educational settings, such systems are often called "student response systems" or "personal response systems." The hand-held remote control that students use to convey their responses to questions is often called a "clicker." More recent entrants into the market do not require specialized hardware, however. There are commercial and open-source, cloud-based tools that allow responses from the audience using a range of personal computing devices such as cell phones, smartphones, and laptops. These types of systems have added new types of functionality as well, such as free text responses that are aggregated into sortable word clouds, as well as the more traditional true/false and multiple choice style questions. This type of system also mitigates some of the concerns articulated below in the "Challenges of audience response" section.

Hardware Based Audience Response: The presenter uses a computer and a video projector to project a presentation for the audience to see. In the most common use of such audience response systems, presentation slides built with the audience response software display questions with several possible answers, more commonly referred to as multiple choice questions. The audience participates by selecting the answer they believe to be correct and pushing the corresponding key on their individual wireless keypad. Their answer is then sent to a base station – or receiver – that is also attached to the presenter's computer. The audience response software collects the results, and the aggregate data is graphically displayed within the presentation for all to see. Some clickers also have additional keys, allowing the presenter to ask (and audience members to answer) True/False questions or even questions calling for particular numerical answers.

...
Wikipedia