Sequelize is an easy-to-use and promise-based Node.js ORM tool for Postgres, MySQL, MariaDB, SQLite, DB2, Microsoft SQL Server, and Snowflake. It features solid transaction support, relations, eager and lazy loading, read replication and more.
An ORM is known as Object Relational Mapper. This is a tool or a level of abstraction which maps(converts) data in a relational database into programmatic objects that can be manipulated by a programmer using a programming language(usually an OOP language). ORMs solely exist to map the details between two data sources which due to a mismatch cannot coexist together.
Visit the following resources to learn more: