juniorHadoop
What is MapReduce?
Updated May 16, 2026
Short answer
MapReduce is a programming model for processing large datasets in parallel.
Deep explanation
It consists of Map (data processing) and Reduce (aggregation) phases. It distributes computation across nodes.
Real-world example
Counting word frequency in large document collections.
Common mistakes
- Thinking MapReduce is real-time processing.
Follow-up questions
- What is combiner in MapReduce?
- Why is MapReduce slow?