JavaScript practiceJavaScript Basics Practice
Build a stronger JavaScript foundation with quick practice questions. These examples focus on the core ideas beginners need before DOM work, frameworks, or interviews.
Example practice questions
Try these samples, then continue into the JavaScript Practice Labfor guided browser-based practice.
1
Which keyword declares a variable that can be reassigned?
Answer: let
2
Which keyword declares a value you do not plan to reassign?
Answer: const
3
Which method adds an item to the end of an array?
Answer: push
4
What does === check in JavaScript?
Answer: Strict equality without type conversion
5
Which syntax creates an arrow function?
Answer: () => {}
6
Which loop can iterate over array values directly?
Answer: for...of
7
What value means a variable has been declared but not assigned?
Answer: undefined