What's the meaning of Definition of Convexity？

Convexity is a mathematical concept that refers to the degree of curvature of a function or a curve. A function or a curve is said to be convex if it curves upwards, meaning that the slope of the function or curve increases as you move along it. In other words, a convex function or curve is one that is always bending outward, or "bulging up" in a consistent manner. Convexity is an important concept in optimization and mathematical modeling, as it helps to identify the optimal solution of a problem. It is also used in finance to measure the sensitivity of a bond's price to changes in interest rates.