Asynchronous code (async code) says: go do something while I do other things, then let me know what happened when the results are ready. Also known as concurrency, async is important in a variety of ...

Let’s understand why we need functions in the first place. Hurrah! we have converted it into functions but wait and ask, ‘Are we using DRY here?’. No, we are still repeating every addition of two ...

Higher-order functions let you treat functions like any other value — passing them around, returning them, and composing them for cleaner, more reusable code. They power everyday tools like map, ...