What is asynchronous processing and why does it improve performance?

Updated May 17, 2026

Short answer

Asynchronous processing allows tasks to run independently without blocking execution.

Deep explanation

It improves throughput by delegating long-running tasks like I/O operations to background threads or queues, freeing the main thread for other work.

Real-world example

Email sending systems using background job queues.

Common mistakes

  • Blocking async calls with synchronous logic.

Follow-up questions

  • What is event loop?
  • What are promises?

More Optimisation interview questions

View all →