Cyberium Infotech Interview Questions and Answers

Arrow functions are a concise way to write functions in JavaScript.

• Arrow functions are written using the '=>' syntax.

• They do not have their own 'this' keyword, instead they inherit it from the parent scope.

• They are often used for short, one-line functions.

• Example: const add = (a, b) => a + b;

Async JavaScript allows for non-blocking code execution, improving performance by handling multiple tasks simultaneously.

• Async JavaScript uses Promises, async/await, and callbacks to handle asynchronous operations.

• It allows for tasks like fetching data from a server or updating the UI without blocking the main thread.

• Example: Using async/await to fetch data from an API asynchronously.

Promises in JavaScript are used to handle asynchronous operations and provide a way to handle the result or error of an asynchronous operation.

• Use .then() method to handle the resolved value of a promise

• Use .catch() method to handle any errors that occur during the promise execution

• Use Promise.all() to handle multiple promises concurrently

• Use async/await to work with promises in a more synchronous way