Explain JavaScript in the context of Next.js.

Short answer: JavaScript runs single-threaded with an event loop. Closures capture lexical scope; promises/async handle I/O without blocking the UI thread.

How to structure your answer (60–90 seconds)

1. Define JavaScript in plain language for Next.js.
2. Context — where it appears in a typical Frontend project.
3. Example — one sentence from work, internship, or a practice app.
4. Trade-off — what you gain vs what you sacrifice.

Real-world example

A React dashboard fetches metrics with async/await, shows loading state, and catches network errors with a toast.

Step-by-step talking points

1. Explain event loop simply
2. Contrast var/let/const and closure use
3. Show async/await for fetch
4. Mention error handling with try/catch

Mistakes to avoid

• await inside forEach
• Mutating shared objects
• Unhandled promise rejections

Junior signal: Focus on clear definitions and one hands-on example—even from a course project or internship.

Practice aloud. Pair this with the full Next.js interview library and timed practice exams on Toolliyo.