Design Links to lookout

What are the design pages one has to lookout for understanding design?

http://www.oodesign.com/

http://www.mindview.net/Seminars/ThinkingInPatterns/

J2EEPatterns:

http://www.corej2eepatterns.com/Patterns2ndEd/

PEAA:
http://martinfowler.com/eaaCatalog/

Design Patterns

This section is started to discuss on design patterns, here i will take one pattern at a time and write the patterns which i read from different sources and provide few examples of the same.


I will be starting up with "Strategy Pattern"


Here i request the readers to post any design pattern which would like to go in details in this blog.