By convention, event handler props should start with on, followed by a capital letter. The stopPropagation() method of the Event interface prevents further propagation of the current event in the capturing and bubbling phases. Stack Overflow for Teams is moving to its own domain! For example, here is a button that doesnt do anything yet: You can make it show a message when a user clicks by following these three steps: You defined the handleClick function and then passed it as a prop to