Who will win the next presidential election? To find out, you might ask each and every registered voter how they plan to vote. But a more practical way to get your answer is to conduct an opinion poll, questioning only a small sample of registered voters. But how can you use the answers of a small group of people to make a prediction that involves many millions of people nationwide?

That’s where statistics comes into play. Statistics is a field of applied mathematics that relies heavily on computers. Using statistics, pollsters can decide who to interview and how to weigh the information they collect to make accurate predictions.