Table 1.

Four V characteristics defining big data

Characteristic	Definition
Volume	The amount of data available, both in terms of the number of samples (length) and the number of variables (depth)
Velocity	The speed at which new data is generated and, thus, the speed at which it must be processed (often in real time)
Variety	The need to integrate different data types, structures, and time scales in different data repositories or domains
Variability	The changing nature of volume, velocity, and variety over time—for example, the addition of new variables, or increasing speed of data accumulation