https://www.techradar.com/news/what-is-big-data

While the origins of the term are elusive, and even debated, big data is one of those concepts that many know about, yet it defies a simple definition. At the heart of big data, as the term directly suggests, is an extremely large volume of data. This is often drawn from diverse sources and even different types of data, which is then crunched through advanced analytic techniques which hopefully pick out patterns that can lead to useful conclusions.

Big data also infers the three Vs: Volume, Variety and Velocity. Volume refers to the size of the data, variety indicates that the datasets are non-homogenous, and velocity is the speed at which the analysis takes place, often with the goal of achieving real-time analysis.