So earlier in the class we mentioned the concept of a Key and inferred some sort of relationship between keys and Joins
While the Key-Join relationship does exist, it is more of a side effect than a primary attribute
A Primary Keys (PK) job is to insure every record in it’s table is unique
A Foreign Keys (FK) job is to keep track of alien Primary Keys (Not of this table)
As it turns out, the “Uniqueness” quality of this field makes it a good candidate for a JOIN, in most instances