The star rating poll is a generic 5 star rating scale.
That's all there is to it. The great thing about a 5 star rating scale is that it's so recognisable you don't need specify what's high or what's low.
When the result is published not only do you see the number of votes for each star you also get a the average response as well.
NOTE: This is a restricted feature for Meetoo Free Education Plans. See this article for more details.