It took me a while to understand the purpose of the useCallback hook.

Let's take an example: imagine you're making your favorite dish, and you're using your favorite recipe for it. Now, whenever you make your favorite dish, you don't want to think about and rewrite the entire recipe each time. Instead, you make a photocopy of your favorite recipe and use it whenever needed. You only update the copy when you want to improve your recipe.

In React, components have functions, which are similar to the recipe for your food. These functions get recreated whenever the component is re-rendered, much like writing your recipe every time you make your favorite dish. This can make the process time-consuming.

useCallback(callback, [dependencies])

Here, the callback is a function that only gets recreated when there is a change in the dependencies. Otherwise, it memoize the function data if the function dependencies are not changed.

The main benefit of the useCallback hook is that it helps in avoiding unnecessary re-renders. This, in turn, aids in optimizing the performance of the webpage.