Within the Overview Tab there are multiple visual representation of your campaign data.
1. This is a line graph of the clicks and opens from your campaign. This shows trend lines and informs you of any correlations between opens and clicks, as well as showing the general trend.
2. Browser Breakdown - Opens shows what browser recipients opened the email on e.g. Microsoft Edge, Mac, etc.
3. Browser Breakdown - Web + LZ Hits shows if the landing zone was clicked on and from what browser.
4. Location Breakdown shows you the country recipients who opened are opening from.