Core Hadoop Concepts

 

Applications are written in high-level code  

• Developers need not worry about network programming, temporal dependencies or low-level infrastructure.

 

Nodes talk to each other as little as possible  

• Developers should not write code which communicates between nodes.
• ‘Shared nothing’ architecture.

 

Data is spread among machines in advance  

• Computation happens where the data is stored, wherever possible.
•  Data is replicated multiple times on the system for increased availability and reliability.