The Freudian slip is an error in human action, speech or memory that is caused by the unconscious mind. The error often appears to the observer as being casual, bizarre and nonsenical.
Although it is certainly true that not all errors done by humans can be explained as Freudian slips, such behaviour is often analyzed on the basis that they may be. "Sometimes the truth has a way of coming out in the most embarrassing and unexpected ways." Although this may be true in many cases, such analysis should certainly be treated by sceptisism.
Freud's theoretical focus on unconscious sexual motivations has resulted in a number of Freudian slip jokes where "embarrassing and unexpected" comments figure prominently. An example: