Open Rate represents each time a user opens an email the first time. Total Opens includes unique opens as well as any forwarded emails or emails opened multiple times by the same user.
Click Reports > Campaign Overviews to see real-time analytics of your campaign. Non-Campaign Specific Reporting On the Reports dashboard, you can see a graph with your historical campaigns. You can see the number of sends for each campaign, open rate, click-through rate, bounce rate, opt-out rate, and spam rate. On the left-hand navigation under Reports, you have options for topline information: Open