data science in big data world facets of data in data science and big data you'll come across many different types of dataand each of them tends to require different tools and techniques the main categories of data are thesestructured unstructured natural language machine-generated graph-based audiovideoand images streaming let' explore all these interesting data types structured data structured data is data that depends on data model and resides in fixed field within record as suchit' often easy to store structured data in tables within databases or excel files (figure sqlor structured query languageis the preferred way to manage and query data that resides in databases you may also come across structured data that might give you hard time storing it in traditional relational database hierarchical data such as family tree is one such example the world isn' made up of structured datathoughit' imposed upon it by humans and machines more oftendata comes unstructured figure an excel table is an example of structured data