Next generation databases mostly addressing some of the points: being non-relational, distributed, open-source and horizontally scalable.
Often more characteristics apply such as: schema-free, easy replication support, simple API, eventually consistent / BASE (Basically Available, Soft state, Eventual consistency) [not ACID (Atomicity, Consistency, Isolation, Durability)], a huge amount of data and more.
A NoSQL (“not only SQL”) database is to meet the requirements by providing a simple and efficient mechanism for data storage and retrieval.
NoSQL Databases vs. Relational Databases
The approach a NoSQL database uses is different from the one used by a relational database.
Relational databases, on the other hand, were not designed to cope with the scale and agility challenges that face modern applications, nor were they built to take advantage of the cheap storage and processing power available today.
The Benefits of NoSQL
When compared to relational databases, NoSQL databases are more scalable and provide superior performance:
Large volumes of structured, semi-structured, and unstructured data,
Agile sprints, quick iteration, and frequent code pushes,
Object-oriented programming that is easy to use and flexible, and
Efficient, scale-out architecture instead of monolithic architecture.