The difference between real-time and relative time ranges in the time picker is that real-time searches display results from a rolling time window, such as the last 15 minutes, while relative searches display results from a set length of time, such as yesterday or last week. Real-time searches do not happen instantly, but rather update periodically based on the refresh interval. Relative searches do not happen at a scheduled time, but rather when the user runs them. Real-time searches do not run constantly in the background, but rather when the user starts them. Real-time searches do not represent events that have happened in a set time window, but rather events that are happening now.