Databases are central components of a back-end developer's journey. They make it possible to store and manage data in greater or lesser quantities to meet various needs and problems.
It is quite complex to define them simply as they are made up of more than 50 years of engineering and innovation to always make our lives simpler (and obviously respond to always more scale). Developers often have a bad habit of underestimating them, but they are often much more efficient than our back-end languages in many tasks.
Each of them will have strengths and weaknesses (whether in the accessibility of the drivers, in the management of persistent or volatile data, in the way of structuring the data, of filtering it, etc.). They form large families just like programming paradigms (Relational, In-memory, Graph etc).
⬅️ 🐢 Node.js: 📦 npm package archive | ➡️ 💾 Database: Influence of Node.js on the chapter