In psychology, the term "Big Five" refers to a personality model made up of five main traits. This model was proposed by the American psychologist Lewis Goldberg in 1981 and developed by Costa and McCrae between 1987 and 1992. It is widely recognised as a benchmark in theoretical personality research and has been used to create the psychological profiles of millions of people around the world.
In-depth analyses have established links between the Big Five test measures and various aspects of behaviour:

Conscientious performance is associated independently of the sector of activity and the evaluation criteria.

Each category of the Diagnostic and Statistical Manual of Mental Disorders (DSM) corresponds to a specific profile of the Big Five, often characterised by a high level of neuroticism and a low level of agreeableness.

The Big Five traits are not entirely independent of each other, which makes some assessments partially redundant when evaluating each category.
In the 2010s, the test associated with the Big Five was used for military, political and partisan purposes, in particular by companies such as SCL Group through its subsidiaries Cambridge Analytica and Aggregate IQ.
Today, this test is widely used and recognised by many companies and industries around the world.