Post modernism/ Intertexuality theories

Intertextuality is the shaping of texts meanings by the use of other texts. John Fiske says there are many types of intertextualities -


Horizontal Intertextuality- 
This is when a text donates references that are on the same level, for example when books make references to other books.


Vertical Intertextuality-
This is found when a book makes a reference to to a film or a song. This can be vice versa as well.


Norman Fairclough distinguishes between :


Manifest Intertextuality-
This includes elements such as presupposition, negation, parody and irony. 


Constitutive Intertextuality-
This shows the importance interrelationship of discursive features in a text such as structure, form or genre. This type of Intertextuality is also known as interdiscursivity. 

Examples
'Material Girl' - paying homage to Marilyn Monroe.