Data can be broken up into 3 different segments, structured, semi-structured and, unstructured.
Structured data: This data has the major advantage of being organised. It generally refers to data that has defined the length and format of data. This is the type of data most useful for analysis.
Semi-Structured data: Stepping down a level, this data is semi-organised. It is generally a form of data that does not conform to the formal structure. An example of this type of data is log files. Usually, this data can be made structured through additional processing before analysis.
Unstructured data: This type of data does not have any organisation properties. It generally refers to data that doesn’t fit neatly into the traditional row and column structure of the relational database. Texts, pictures, videos etc. are examples of unstructured data which can’t be stored in the form of rows and columns and is therefore difficult to process through conventional means.