In Formula 1, DNF stands for "Did Not Finish". It is used to indicate that a driver did not complete the race due to various reasons such as an accident, mechanical failure, or disqualification. A DNF is an important statistic in F1 racing as it shows how reliable and consistent a driver and their team are in completing the race. If a driver receives a DNF, they will not receive any points for that race and will not be counted among the finishers.