What is the difference between DBMS and RDBMS?

Question

After reading some answers on different websites I am confused now. So, it would be helpful to mention the key difference between DBMS and RDBMS and any relation between the

Answer 1

DBMS: is a software system that allows Defining, Creation, Querying, Update, and Administration of data stored in data files.

Features:

• Normal book keeping system, Flat files, MS Excel, FoxPRO, XML, etc.
• Less or No provision for: Constraints, Security, ACID rules, users, etc.

RDBMS: is a DBMS that is based on Relational model that stores data in tabular form.

• SQL Server, Sybase, Oracle, MySQL, IBM DB2, MS Access, etc.

Features:

• Database, with Tables having relations maintained by FK
• DDL, DML
• Data Integrity & ACID rules
• Multiple User Access
• Backup & Restore
• Database Administration