DFS (Daily Fantasy Sports)

Short-duration fantasy sports contests — one day, one week, or one game — where users assemble lineups and compete for cash prizes. DraftKings and FanDuel built the category before pivoting both companies into sportsbooks. Legally classified as games of skill in most states; subject to gambling-style consumer-protection scrutiny anyway. The on-ramp that taught a generation of fans to wager on outcomes.