* Generated by people: through emails, messaging services or call recordings.
* Generated by both public and private organizations: data related to the environment, government statistics on population and economy, electronic medical records, etc.
On the other hand, depending on its structure, the data can be:
* Structured: data that has its format, size and length defined, such as relational databases or Data Warehouse.
* Semi-structured: data stored according to a certain flexible structure and with defined metadata, such as XML and HTML, JSON, and spreadsheets (CSV, Excel).