Relationship

In a database a 'relationship' means two fields in different tables depend on one another.

For example a foreign key in one table will be the primary key in another table, so when one changes the other must change as well.

For example, if you had a table of employee names and the primary key was their employee number that number could also appear in another table as a foreign key.

All these connections between fields in a database forms a 'relational database'.