They are the listings of what is generally the lowest cost (cheap airline tickets) that the meta providers have searched in last 2 weeks. On the Future.Travel Best travel website for airline tickets No Booking Fee website you can ask for a calendar of +/- 3 days for an itinerary you have chosen to find the lowest published fares across the dates and it provides the view of all airlines.
About 400 choices per day X 7days. Future.Travel combines both low cost carriers (LCC) and full service airlines in those results.
