Phenomenology is the study of structures of consciousness from a first-person point of view. It studies how people experience phenomena through concepts like perception, memory, and judgment. The central focus is on intentionality and how experiences are directed at objects. Phenomenology was introduced by philosophers in the 18th century and defined by Edmund Husserl in the early 20th century as the science of the essence of consciousness. There are different types of phenomenological approaches that focus on topics like existence, history, and realism.