What is the difference between == and === in JavaScript?
Explain the difference between loose equality (==) and strict equality (===) operators in JavaScript. When would you use one over the other?
Node.js interview questions covering event loop, async patterns, Express/Fastify, package management, and server-side JavaScript.
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Questions in database
Explain the difference between loose equality (==) and strict equality (===) operators in JavaScript. When would you use one over the other?
Explain what closures are in JavaScript. Provide an example of when you would use a closure and explain how it works.
Write a debounce function that delays invoking a function until after a specified wait time has elapsed since the last time it was invoked.
How does the event loop work in Node.js? Explain the different phases and how async operations are handled.
Explain the differences between var, let, and const in JavaScript. When would you use each one?
Write a function that creates a deep copy of a JavaScript object. Handle nested objects, arrays, and edge cases like circular references.
Explain the difference between Promise.all() and Promise.allSettled() in JavaScript. When would you use each?
Write a throttle function that limits the rate at which a function can be called. It should invoke the function at most once per specified time period.
Implement Promise.all in JavaScript without using the built-in method. Handle success and failure cases correctly.