1.What is a relational database management system (RDBMS)?
    -A database that stores data in tables

2. What is SQL?
    -The standard data model and language for relational databases

3. What is an ER model?
    -An abstract model that views relationships

4. Define the following terms: One-to-one relationship, one-to-many relationship, and many-to-many relationship.
    - One-to-one relationship
        - Relationship where each record in Table A can be related to one (only one) record in Table B
        - Vice Versa for Table B to Table A

    - One-to-many relationship
        - Relationship where a single record in Table A can be related to one or more records in Table B,
          but a single record in Table B can onlu be related to one record in Table A.

    - Many-to-many relationship
        - Relationship where many record in one table match many records in another table

5. What is the purpose of a primary key? Why should it be unique?
    -Primary key is used to identitfy each row in a table, it should be unique since it identifies each row