represent complex data relationships, improve database performance and impose a database standard, depicts both one-to-many (1:m) and many-to-many (m:n) relationships
1) represent complex data relationships efficiently, 2)improve database preformance and impose database standard, 3)allow a record to have more than one parent, 4) one-to-many relationships and m:n
is &"self-describing&" and it contains within itself all information about itself (aka metadata)