We have two keywords Async and Await. We use async in front of a function declaration or function expression. The async keyword is used to define a particular function as an asynchronous function. When we put the Async keyword at the beginning of our function, we get a promise.
Promise is easier to write and implement than callbacks. A promise is simply an object that represents the completion or failure of a process. It's usually something that takes time. When we use a library like Axios we return a promise and when we request data from api this process may take time and this value may never come back...
Callbacks are functions passed to other functions to be called inside the outer function. it is any function called by another function using a parameter. when we pass a function to another function and it is executed in that function, we can call it a callback.