Competitors report provides insights into organic traffic distribution for the tracked keywords between your domain and competition. The table shows percentage of traffic that you receive and the traffic share of top performers for your search queries. This gives you an understanding of your online presence in the industry and visibility for a group of keywords rather than rankings data on individual keywords. A best practice for measuring the market share would be to split your desired keywords into groups according to the target URLs (you'll see how to assign and track a target URL for a keyword in the next report) by labeling them.
Below is the Top competitors table that shows the Top 20 competitors for tracked keywords based on the visibility in search.
History report shows you how the visibility and, respectively, traffic share of the most powerful domains has been changing over time that you're tracking your keywords. You can choose custom periods in the calendar.
Competitors changes report shows the changes in the visibility score of the Top 10 domains for your keywords