Recursion has been defined in different ways, it is present in different fields and its possible origin has been traced in different human activities or cultural manifestations. This chapter discusses the definition of recursion in mathematics, language and computer science, shows its presence in philosophy or art, and analyses its possible origin in the first tools manufactured by humans and in basic actions such as inserting one gemetric body into another. These notes show recursion as a complex property strongly rooted in human cognition and behaviour.