Flexiele Frontend Developer Intern Interview Questions and Answers

Same Origin Policy is a security feature in web browsers that restricts web pages from making requests to a different domain.

• It prevents malicious scripts from accessing sensitive data from other websites

• It applies to all web content, including JavaScript, CSS, and images

• Cross-Origin Resource Sharing (CORS) is used to bypass the Same Origin Policy

• Example: A script from www.example.com cannot access data from www.anothe

Redux is a predictable state container for JavaScript apps.

• Redux is a library for managing application state.

• It provides a single source of truth for the entire application state.

• Redux follows a unidirectional data flow pattern.

• Actions are dispatched to update the state, which triggers a re-render of the UI.

• Redux can be used with React, Angular, Vue, and other frameworks.

Thunk is a function that delays the evaluation of an expression.

• A thunk is a function that wraps an expression to delay its evaluation.

• It is commonly used in Redux to handle asynchronous actions.

• Thunks are used to dispatch actions that return a function instead of an object.

• Thunks can be used to handle side effects in React components.

Callbacks are functions passed as arguments to other functions and executed later.

• Callbacks are used for asynchronous programming.

• They allow a function to be called when an event occurs.

• They can be used to handle errors in asynchronous code.

• Examples include event listeners and setTimeout() function.

Promises are objects that represent the eventual completion or failure of an asynchronous operation.

• Promises have 3 states: pending, fulfilled, or rejected

• Pending is the initial state when a promise is created

• Fulfilled means the operation completed successfully

• Rejected means the operation failed

• Promises can be chained using .then() and .catch() methods

Worker threads allow for parallel execution of JavaScript code in the browser or Node.js environment.

• Worker threads can be used to perform CPU-intensive tasks without blocking the main thread.

• They can also be used to communicate between different scripts or modules.

• In Node.js, worker threads can be created using the 'worker_threads' module.

• In the browser, worker threads can be created using the 'Worker' constructor.

• Exa...read more