What is Mentimeter?
Mentimeter is an interactive presentation with student response system. Slide show on the student side progresses along with the teacher. If the slide contains a question, students can respond from their devices.
Note that the free version of Mentimeter has very limited functions and now there are several free alternatives, such as Quizizz and Wooclap.
Create and manage slides: https://www.mentimeter.com/
Student/Audience access: https://www.menti.com/