The sections are a webflow cut up in multiple sections, which can be pages. In this example you see the pages of a webflow and their emotion scores. The emotion scores that are displayed are the average scores of the group per section.
This page is used to find out which pages are the bottlenecks within the user flow. Pages containing high frustration levels are most likely the ones you can improve and perform A/B tests on.
When you hover over a colored bar, it shows you what the average emotion score is. When you click on it you will go to the Section insights page.