English Quiz - async/await, scope

1. Explain the difference between Async/Await and Promises.

1. Syntax: Promises use a chaining syntax with '.then' and '.catch' to handle asynchronous operations. On the other hand, 'async/await' provides a more concise and synchronous-looking syntax for writing asynchronous code. it improves code readability and maintainability.
2. Error handling: With promises, you handle errors using '.catch' at the end of the chain, while 'async/await' allows you to handle errors using standard 'try/catch' blocks.

2. What is scope in JavaScript?

• Scope refers to accessibility and visibility of variables, functions, and objects in JavaScript. It determines where variables and functions are defined and where they can be referenced.

3. Explain the difference between ‘visibility: hidden’ and ‘display:none’.

• 'visibility: hidden' hides an element while still occupying space in the layout and maintaining its presence in the DOM, whereas 'display: none' hides an element, removes it from the layout, and removes it from the DOM.

4. What is closure in JavaScript?

• A closure is a function that remembers its outer variables and can access them. In JavaScript, all functions are naturally closures. They automatically remember where they were created using a hidden [[Environment]].

참고

• JavaScript Info - Variable scope, closure