Setting up a connection and all the basics for Sequelize.

Source: https://sequelize.readthedocs.io/en/v3/docs/getting-started/

Object-relational mapping (ORM, O/RM, and O/R mapping tool) in computer science is a programming technique for converting data between incompatible type systems using object-oriented programming languages. This creates, in effect, a "virtual object database" that can be used from within the programming language.