On the left is the pit board you'll see during practice sessions; the top number displays the speed of your last completed lap, while the bottom number is your best speed so far in the current session. (A session ends when you return to the garage.) Here, the driver just turned his fastest lap of the session.

The pit board on the right is the one you'll see during the race each time you cross the start/finish line. "P" indicates your current position in the field, "L" indicates how many laps remain in the race, and the next two lines represent the cars in front of and behind you and your distance from each of them: here, we're 0.1 seconds behind the #8 car and 0.9 seconds in front of the #12 car. Note that these numbers are from the previous time you crossed the start/finish line (one lap prior), unlike the function key displays which are accurate as of the current lap.