Salesforce JavaScript Developer Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

An asynchronous function in JavaScript is defined as a function that returns a promise and allows the use of the await keyword. This is a crucial aspect of modern JavaScript development, especially when dealing with operations that take time to complete, such as network requests or reading files.

When a function is marked as asynchronous using the `async` keyword, it automatically returns a promise. This promise represents the eventual completion (or failure) of the asynchronous operation, allowing developers to manage async actions more effectively. The inclusion of the `await` keyword within an asynchronous function allows the program to pause execution until the promise is resolved, making the code easier to read and understand. Essentially, it provides a way to handle asynchronous code in a more synchronous-like manner, improving both readability and maintainability.

The other options do not accurately capture the nature of asynchronous functions in JavaScript. While synchronous functions execute in a sequence and can lead to blocking behavior, asynchronous functions are designed to run without blocking the event loop, enabling more efficient execution of code. The mention of callbacks in one of the options refers to an earlier style of handling asynchronous behavior (such as using functions that can be called upon the completion of an operation) but does not encompass the broader capabilities and structure offered by async