Apollo Computer Education Front end Developer Interview Questions and Answers

A promise is an object representing the eventual completion or failure of an asynchronous operation.

• Promises are used to handle asynchronous operations in JavaScript.

• They can be in one of three states: pending, fulfilled, or rejected.

• Promises can be chained using .then() to handle success and .catch() to handle errors.

• Example: Fetch API returns a promise when making an HTTP request.

Types of data include numerical, categorical, ordinal, and nominal data.

• Numerical data: Data that can be measured and expressed in numbers (e.g. age, height, weight).

• Categorical data: Data that represents categories or groups (e.g. color, gender, type of car).

• Ordinal data: Data with a natural order or ranking (e.g. rating scale from 1 to 5, education level).

• Nominal data: Data that represents names or labels without any