Well patterns are a way to label commonly used ways of coding. It helps to know ur labels (read: patterns) to communicate with other developers about a certain software aprouch. Don't get fooled by the fancy names, you prob. allready have used a lot of them without knowing it ;-)

The pseudo pattern is mostly used in webshops, it means that you log an user his actions but only let him/she sign in when its really needed. So you can add items to ur cart but only have to sign in when ur going to check out.

A book I still need to read is that of the gang of four

edit:
just amazoned it:
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"Design Patterns. Elements of Reusable Object-Oriented Software."Erich Gamma; Gebundene Ausgabe; EUR 45,03 Verkauft von:Amazon.de
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"Head First Design Patterns."Eric Freeman; Broschiert; EUR 22,26

Creational, Structural & behavioral patterns

also see other posts on patterns. patterns posts