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Hi,
There are design patterns that use Spark extensively. I am new to this area so I would appreciate
if someone explains where Spark fits in especially within faster or streaming use case.
What are the best practices involving Spark. Is it always best to deploy it for processing
engine, 
For example when we have a pattern 
Input Data -> Data in Motion -> Processing -> Storage 
Where does Spark best fit in.
Thanking you