Seminar paper from the year 2008 in the subject English Language and Literature Studies - Linguistics, grade: 2,3, University of Hamburg (IAA), course: Seminar Linguistik: Semantics: Understanding the meaning of words and their combinations, 18 entries in the bibliography, language: English, abstract: This term paper deals with the development of categorisation, concepts and prototypes in terms of cognitive psychology. In recent decades, prototype semantics has begun to gain an important role in linguistics and led to a pardigm shift. This is proved by research in cognitive psychology. People have a command of categorising, all times. Without the process of categorisation, our brain would be overstrained because the flood of information, the brain receives, has to be memorised and, thus, categorised, in a certain way. First of all, I will explain the importance of categorisation and concepts in everyday life, then I will introduce some forms of categorisations (Artistotle's traditional view and the prototype theory), explain them by giving examples, analyse and criticise them, insofar as I consider them critisisable. In section three I will describe the development of categorisation, concepts and prototypes with regard to childhood. One important question in this context will be whether prototypes are changeable in the course of life? The process of categorisation by having some concepts in mind, is an important factor in human existence. Human beings categorise what they perceive by comparing the perceived object with their mentally represented concept. All people think categorically because it helps them to establish a certainty and order. People need certainty and order, for not drowning in chaos. Without categorising, human beings would have to store the information of each single element which encounters him. Categories and concepts help us to understand the world, its elements and we establish a form of cohesive network by building up concepts and categories and having prototypical exemplars in mind. If we see people, we categorise them, whether it is their outward appearance or how they talk or how they behave towards us. By doing this, we sometimes practise a form of pigeonholing other people. This pigeonholing, though, is human, as we cannot cease to categorise what we perceive. 'Categorization provides the gateway between perception and cognition. After a perceptual system acquires information about an entity in the environment, the cognitive system places the entity into a category'.