Both of those defence mechanisms are activated when information needs to be kept out of our conscious awareness. Repression occurs when we do this unconsciously, while suppression when we do it consciously. However, these memories don't just disappear; they continue to influence our behaviour.

Denial is one of the best-known defence mechanisms which blocks us from admitting or recognising that something has occurred or is currently occurring. Denial's purpose is to protect the ego from things with which the individual cannot cope. It is often the case that even though enough evidence is pointing that something is true, the person will choose to deny its existence or truth because it is too painful to handle.

One of them is what we call "projection" (or "externalisation"). This is when people mistakenly think that the problem is caused by other people around them instead of themselves. This defence mechanism makes us ascribe unacceptable qualities and feelings of our own personality to other people. Example: Some people are not in touch with their anger. They project their anger onto others and begin to believe that it is the "others" who are angry. The strategy of projection has as a primary goal to reduce anxiety. It does this by allowing the expression of the feeling, but in a way that the ego cannot recognise as its own. Therefore stress is temporarily reduced.

Let's stick with the anger example. Displacement occurs when we take out our feeling of anger to a person or object, which is less threatening than the cause of irritation. Example: Instead of expressing anger at your boss, which may have severe consequences, you decide to take it out to your spouse, friend, pet etc

According to Freud, intellectualisation involves engrossing oneself so deeply in the reasoning aspect of a situation that you completely disregard the emotional aspect involved. In other words, thinking is used to block feeling. The intellectual analysis of a devastating event helps us to distance ourselves emotionally from anxiety-provoking stimuli.

Rationalisation is a defence mechanism that involves explaining an unacceptable behaviour or feeling rationally or logically, avoiding the behaviour's true reasons. For example, a person who is rejected for a date might rationalise the situation by thinking they were not attracted to the other person anyway. An employee might blame their poor performance on their manager rather than their own lack of preparation for the job. Rationalisation job is to prevent anxiety and also protect our self-esteem.