The variety of big data comes from having a multiplicity of data sources that generate data and the different formats of data that are produced.

This results in a technological challenge for the recipients of the data who have to process it. Digital cameras, sensors, the web, cell phones, and so on are some of the data generators that produce data in differing formats, and the challenge is being able to handle all these formats and extract meaningful information from the data. The ever-changing nature of data formats with the dawn of the big data era has led to a revolution in the database technology industry with the rise of NoSQL databases, which handle what is known as unstructured data or rather data whose format is fungible or constantly changing.