This is the first of two episodes where Arno and Alex discuss eXtreme Programming in se-radio's development process track. eXtreme Programming (XP) revolutionized the way of thinking about software development methodologies and helped to make the agile movement popular. In this episode they discuss the very basics of XP, its value system, principles and the basic practices used in an XP project. The second episode will continue the introduction adding the missing practices and how to introduce XP into projects.