Hadoop VS Spark: Which is the best Data Analytics engine?

@machinelearnbot 

In the book Hadoop: The definitive guide, Tom white quotes Grace Hopper, "In pioneer days they used oxen for heavy pulling, and when one ox couldn't budge a log, they didn't try to grow a larger ox. We shouldn't be trying for bigger computers, but for more systems of computers." For long Hadoop has been the data analytics system preferred by businesses all over. The recent entry of the spark engine has however given businesses an option other than Hadoop for data analytics purposes. A lot of discussion among experts in the field of big data analytics is over which of the two data analytics engines, the Hadoop or the Spark, is the better performer when it comes to applications in business.