What DBMS have you worked with? What is a relational DBMS?

Worked with various DBMSs, including PostgreSQL, MySQL, SQLite, and Microsoft SQL Server. A relational DBMS is a database management system that stores data in the form of tables related to each other by specific keys. The main idea is representing data as rows and columns, where each table corresponds to a specific object or concept, and relationships between tables ensure integrity and enable complex queries using SQL. For example, a "Users" table can be linked to an "Orders" table via a foreign key, allowing easy retrieval of all orders for a specific user.