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.
JavaScript basics practice should connect syntax with behavior. A learner needs to know the keyword or method, but also what that choice does when code runs.
Work through variables, arrays, equality, loops, and functions in short rounds. When a pattern feels easy, combine two ideas, such as an array question that also uses a loop or function call.
- let, const, arrays, and strings
- Strict equality and common operators
- Loops, functions, and undefined values
Example practice questions
Try these samples, then continue into the JavaScript Practice Labfor guided browser-based practice.
Which keyword declares a variable that can be reassigned?
Answer: let
Which keyword declares a value you do not plan to reassign?
Answer: const
Which method adds an item to the end of an array?
Answer: push
What does === check in JavaScript?
Answer: Strict equality without type conversion
Which syntax creates an arrow function?
Answer: () => {}
Which loop can iterate over array values directly?
Answer: for...of
What value means a variable has been declared but not assigned?
Answer: undefined