What is Big-O notation?

Updated May 17, 2026

Short answer

Big-O describes algorithm performance growth rate.

Deep explanation

It abstracts constants and focuses on dominant terms. It helps compare efficiency across algorithms.

Real-world example

Search engines choosing efficient ranking algorithms.

Common mistakes

  • Confusing Big-O with actual execution time.

Follow-up questions

  • What is O(1)?
  • What is O(n²)?

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