This post is from a low-reputation account and contains an unverified outbound link. Be cautious before clicking external links.
It is a meter through which AC volt, DC ampere resistance and continuous check are done. this is an electronic measuring instrument that combines several measurement functions in one unit. in this video you can learn about Multi meter
https://www.fully4world.com/2018/10/16/what-is-multi-meter-and-use-it-function-fully4world/