The colour wheel theory of love is an idea created by the Canadian psychologist John Alan Lee that describes six love styles, using several Latin and Greek words for love. First introduced in his book Colours of Love: An Exploration of the Ways of Loving (1973), Lee defines three primary, three secondary, and nine tertiary love styles, describing them in the traditional colour wheel. The three primary types are Eros, Ludus, and Storge, and the three secondary types are Mania, Pragma, and Agape.