10 Questions About Javascript

Q: What is the difference between “Null” and “Undefined”?

Q: What is the difference between “==” and “===”?

Q: What is hoisting in a variable?

Q: What is the difference in hoisting between var and let?

Q: What is the difference between let and const?

Q: What is the “NaN ” ?

Q: Which company developed JavaScript?

Q: What is ‘this’ keyword in JavaScript?

Q: What is an undefined value in JavaScript?

  • Variable used in the code but doesn’t exist.
  • Variable is not assigned to any value.
  • Property does not exist.

Q:What are the types of errors in JavaScript?

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Ahsan Ullah

I am a web developer. I have excellent skills in web development. Worked in HTML, CSS3, Reactjs,Nextjs, Javascript, TypeScript, Bootstrap, and MaterialUI.