Zero- and one-day options give investors the ability to bet on the daily moves of the S&P 500. In recent months, both big institutional investors and retail traders have gotten in on the action, creating a boom in trading volumes of these short-lived contracts and sparking an intense debate over their effect on the market. So what exactly is driving their popularity and why are some Wall Street analysts so divided on whether such options will cause a rerun of the “volmageddon” that we saw back in early 2018 and that caused a big drop in stocks? Nomura Securities International Inc. strategist Charlie McElligott walks us through these new trading contracts, explaining how they work, why people are snapping them up, and what their impact on the market could be.