2018 daily fantasy football preview: What is DFS, and how do I play DFS? A guide to navigating NFL daily fantasy football on DraftKings and FanDuel. Check out our full 2018 Fantasy Football Draft guide! Share this story Share All sharing options for: 2018 daily fantasy football preview: What is DFS, and how do I play DFS? Geoff Burke-USA TODAY Sports NFL preseason games? They’re not just for the players on the field. In the wonderful world of Daily Fantasy Sports, there is no such thing as games that don’t count.