Convexity in economics

Convexity in economics is like a curved hill. It is a measure of how the price of something, like a stock or bond, changes when interest rates change. If the hill is curved, then when interest rates change, the price of the stock or bond will usually change more or less than the amount of the change in the interest rate. If the hill is steep, then the price will change more, and if the hill is flat, the price will change less.