The Session Window comes up the first time a session is run.
The Session Info Window shows key events for the session in progress. The Log Window shows detailed information on the various actions taking place. The Status Panel shows the highlights of current events as well as the progress for a given series, the exposure etc. Clicking on and dragging the Splitter Bar allows customization of the size and composition of the Session Window. Here is another arrangement that minimizes screen real estate by dragging the splitter bar and resizing the window:
Here the Session Info Window has been minimized by dragging the splitter bar to the left and the overall window has been reduced to show only the Log Window and Status Panel.
You can customize the Session window to fit the way you like to work.