Big Data. Big. Data. We hear the term frequently used to describe data of unusual size or generated at spectacular velocity, like the amount of social data that Facebook has amassed on us (30 PB in one cluster) or the rate at which sensors at the Large Hadron Collider collect information on subatomic particles (15 PB/year). And it’s often deemed “unstructured or semi-structured” to describe its lack of apparent, well, structure. What’s meant is that this data isn’t organized in a way that can directly answer questions, like a database can if you ask it how many widgets you sold last week.