What is MapReduce used for

Now a days MapReduce use mani tech joint company for their data processing. such as:

At Google

• Index construction for Google Search
• Article clustering for Google News
• Statistical machine translation
• wordcount, adwords and pagerank

At Yahoo

• “Web map” powering Yahoo! Search
• Spam detection for Yahoo! Mail

At Facebook

• Data mining
• Ad optimization
• Spam detection

At research

• Astronomical image analysis (Washington)
• Bioinformatics (Maryland)
• Analyzing Wikipedia conflicts (PARC)
• Natural language processing (CMU)
• Particle physics (Nebraska)
• Ocean climate simulation (Washington)
• and so on

MapReduce provides

• User-defined functions
• Automatic parallelization and distribution
• Fault-tolerance
• I/O scheduling
• Status and monitoring