Foreign key for content type
It is possible to reference content types from one another but not with the core field system. There are currently 3 modules that offer this functionality:


References
Entity Reference
Relation


I'll let you read the module pages yourself to decide which one is best for your use case.

Each of the modules provides a field type that you can attach to one content type to reference another. The fields behave just like any others in the system and so can have a static or unlimited cardinality.