What does "NoSQL" mean?

"NoSQL" refers to a class of databases that don't use the relational model with tables, rows, and rigid schemas. Instead, such databases store data in other formats - for example, as documents, key-value pairs, graphs, or columns.

#NoSQL's main traits

• no fixed schema (objects with different structures can be stored)
• horizontal scaling (data can easily be spread across many servers)
• flexible data models (JSON, key-value, graph, and so on)
• usually optimized for speed and large data volumes

#Examples of NoSQL databases

#When NoSQL is used

• when data doesn't fit tables well
• when the structure changes often
• when high speed and scalability are needed

Summary: NoSQL is the general name for non-relational databases, which use more flexible storage models instead of rigid tables and relationships.