What is a recommendation system?

Updated May 16, 2026

Short answer

A recommendation system suggests relevant items to users based on behavior, preferences, or item similarity.

Deep explanation

Recommendation systems analyze user-item interactions, metadata, or both to predict what a user is likely to engage with. They are widely used in e-commerce, streaming platforms, and social media to improve engagement and retention. The core idea is to reduce information overload by ranking items by relevance.

Real-world example

Netflix suggesting movies based on viewing history.

Common mistakes

  • Thinking recommendation systems only use user ratings.

Follow-up questions

  • What are main types of recommendation systems?
  • Where are recommendation systems used?

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