This is one of the most commonly asked questions when people begin to study Psychology. Psychology is the study of human behaviour. So whilst psychologists can't read exactly 'what' you are thinking, we can infer 'why' people appear to think and behave in the ways they do, by looking at how they are affected by their biology, psychology and environment. However, recent neuroscientific advancements in the field have led to the belief that we are getting closer to being able to read minds. Brain imaging technology can now track activation in areas of the brain that are associated with thinking about certain things - such as spatial memories. For example, by studying the neural activity patterns in regions of the brain associated with spacial navigation/memory (such as the hippocampus), psychologists could infer where video game players are within a virtual environment. Whilst we are a long way off, this could be the first step to being able to read minds.