Data, Types of Data & NoSQL

Data -

Data is nothing but the fact, either we can call it as information.
Database contain several Table, Table having Rows & Column, single cell value in Table which represent as Data. 
Data refers to all the single items that are stored in a database. 

Data in different format -

Text / Number /Date
File - JSON, CSV, XML etc. 
Image
Audio 
Video

Files  like txt, word, PDF.

based on format it categorized into different types, 

Types of Data -

Structured - Text / Number /Date
Semi Structured  -JSON, CSV, XML etc.
Un Structured-  Image, Audio Video

structured - 

The data is stored in an tabular format, each row and column contributing to a specific data type. As structured data is schema dependent, it is a little difficult to scale it for large databases.

It is also known as "schema dependent" data.

example 

RDBMS system example - SQL SERVER, Oracle, MySQL

Semi-structured 

Semi-structured data is a type of structured data that lies midway between structured and unstructured data.
examples of semi-structured data are CSV, XML, and JSON. Semi-structured data is more complex than structured data but less complex than unstructured data.

xml file
<Node>
<Firstname>Rahul</Firstname>
<LastName>Sable</LastName>
</Node>

json File

                "Node": 
{
"Firstname": "Rahul",
"LastName": "Sable"
}

Unstructured 
It is also known as "schema independent" data.
Examples of unstructured data include text, video files, audio files, Image, files.
non-relational or NoSQL databases are the best fit for managing unstructured data.

NO SQL - 

4 types, 

               1) document

               2) key-value

               3) wide-column

               4) graph