promisified

Promisified refers to the process of converting a function that uses callbacks into one that returns a Promise. Callbacks are a common pattern in JavaScript for handling asynchronous operations, where a function is passed as an argument to another function and is executed later, typically after an operation completes. While effective, managing multiple nested callbacks can lead to "callback hell," making code harder to read and maintain.

Promises, on the other hand, represent the eventual result of an asynchronous operation. They provide a cleaner way to handle asynchronous code by allowing for chaining operations and more structured error handling. A promisified function wraps the original callback-based function. When the promisified function is called, it creates a new Promise. The original callback-based function is then invoked with a custom callback that resolves the Promise with the success value or rejects it with an error. Libraries like Node.js's `util.promisify` and popular third-party libraries like Bluebird offer utilities to easily promisify existing callback-style functions, streamlining asynchronous programming in JavaScript. This conversion significantly improves code readability and maintainability.