I took a course on Big Data that explained how there is a distributed architecture that enables a "master" to send out the job to vast army of "slaves" to complete the processing. However, how do I explain this in a succinct and effective way to the students?
In a word, YouTube.
I found this video that gives a pretty good overview of Big Data, but it's real value is how it explains how Hadoop works at a high level (go to 4:10):
Of course, we will be covering social media later in the term :)