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The main aim of this work is to make a comprehensive study of a weaker version of normality called pi-normality. We give a survey study of pi-closed, pi-open, pre-closed and pre-open sets, which are the keys of both pi-normality and pi-pre-normality.The notion of pi-generalized closed sets is used to obtain various characterizations and preservation theorems of pi-normality. Some different results are presented in this work.