Partitioning Sharding is a technique used to improve the scalability and performance of databases by dividing the data into smaller partitions, or shards.

Replication There are several reasons why you might want to replicate data:

Storage and Retrieval It’s an oversimplification but in essence database has to do only two things:

Encoding and Evolution In order to make changes to an application’s features, it is necessary to also make changes to the data that the application stores.

Data Models and Query Language For the most application it is true that they are built by layering data models on top of each other.

Three Concerns in Software Systems As we start the system design journey first I would really recommend you to check Designing Data-Intensive Applications or as people in tech community called it the big red pig book :D Most of the posts in the fundamentals were actually inspired by this book and it’s great author Martin Kleppmann.