A quantitative fund is like a piggy bank that uses lots of math and computer science to make money grow. People who run the fund take different pieces of information, like how much a company earns or how many people are buying a product, and put it into special computer programs that crunch the numbers and make predictions about what stocks to buy or sell. Think of it like solving a puzzle, but instead of using your hands like with a puzzle, people use computers and numbers to solve the mystery and hopefully make more money.