Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. In psychology, phenomenology is used to refer to subjective experiences or their study. The experiencing subject can be considered to be the person or self, for purposes of convenience. In phenomenological philosophy (and particularly in the work of Husserl, Heidegger and Merleau-Ponty) ''experience'' is a considerably more complex concept than it is usually taken to be in everyday use. Instead, experience (or Being, or existence itself) is an ''in-relation-to'' phenomena, and it is defined by qualities of directedness, embodiment and worldliness which are evoked by the term ''Being-in-the-World''.