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Javascript interviews questions and answers with code

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JavaScript interview questions along with answers and code examples 1. Question: What is the difference between null and undefined in JavaScript? Answer: null is a deliberate assignment representing the absence of any object value. undefined is a variable that has been declared but not assigned any value. 2. Question: Explain the concept of closures in JavaScript. Answer: Closures occur when a function is defined inside another function, allowing the inner function to access the outer function's variables. This creates a scope chain. function outerFunction() { let outerVariable = 'I am outer!'; function innerFunction() { console.log(outerVariable); } return innerFunction; } let closureExample = outerFunction(); closureExample(); // Outputs: I am outer! 3. Question: What is the event loop in JavaScript? Answer: The event loop is a mechanism that handles asynchronous tasks in JavaScript. It continuously checks the call stack and the callback queue. When th