The default view of the graph shows a graph of all traffic and all unique traffic in the selected time-period. When you login, the time-period is the last seven days, so this is a quick overview of all your marketing, with the total visitors and total repeat visitors on the left, where repeat visitors are people who clicked on the same marketing link more than once:

When you change your filters or time-period, the graph and reports will change to only show marketing that matches those filters, so it's like having many dashboards in one. And, if that time-period includes right now, the graph will update every 30 seconds, with live data as it comes in. 

The graph can show anything from any of the reports below the graph, which allows you to see correlations in your data, which would be otherwise very difficult to confirm. To do that, select any report below, hover over the row you want to graph, and click the graph button that appears:

As soon as you click it several things will happen:

  1. The item will be graphed in the graph.
  2. The item will be listed in the legend to the right of the graph. The icon will be the same as the report it came from, in this case a link to show it came from the redirect link report. And it will be the colour of the line in the graph.
  3. The button on the row will change to one to remove that from the graph.
  4. The icon on the row will change to be the colour of the line in the graph, so you know that row is graphed at a glance.

Since you already have the graph of all your traffic, anything you graph from the reports will likely be very small and hard to see, so you might want to hide the graph of total visitors and unique visitors. You do that by clicking on each of those buttons to the left of the graph:

Now, you see that the total visitors and repeat visitors are grey and the line you're graphing graphing has popped up to take up the whole graph, so you can see it. Clicking on those buttons again will show the total and repeat visitors in the graph again.

You can add items to the graph from any of the reports below. So, for example, you could graph different groups together, to compare how much traffic is coming from redirect links in your "Pay-Per-Click" custom group vs. your "Blog Comments" custom groups, if you use unique links in each group. 

Or, you could compare things from different groups. So, if you want to see specific information together, you can. Perhaps you're most interested in some specific redirect links, destinations, and traffic sources. You can put them all up there, and watch the traffic from them live, as I'm doing here. Notice that the icons in the legend are from three different reports.

Once an item is in the legend, you can hover your mouse over the row in the legend to get options to either remove the item from the graph, or temporarily hide it, which is useful if it's a big item that's eclipsing other data:

NOTE: If you change change your filters and time periods, those items will update to reflect those changes, including the total and unique visitors, so if you see numbers that don't make sense, check to see if you're looking at only a portion of your data.