Sigmund Freud posited that incest and patricide were the only two universal taboos and formed the basis of civilization.^[10] However, although cannibalism, in-group murder, and incest are taboo in the majority of societies, modern research has found exceptions for each and no taboo is presently known to be universal.^{[11][12][13][14][15][16][17][18]}

Common taboos involve restrictions or ritual regulation of killing and hunting; sex and sexual relationships (primarily incest, necrophilia, miscegenation, adultery, fornication, pedophilia, homosexuality, intermarriage, bestiality, and masturbation); reproduction (abortion, infanticide); the deceased and their graves; food and dining (primarily cannibalism and dietary laws such as vegetarianism, kashrut, and halal); and bodily functions (primarily menstrual cycles, but also defecation and urination).^{[citation needed]}

Taboos often extend to cover discussion of taboo topics, resulting in euphemisms and replacement of taboo words.^{[citation needed]}

The word "taboo" gained popularity at times, with some scholars looking for ways to apply it where other English words had previously been applied. For example, J. M. Powis Smith, in his "The American Bible" (editor's preface 1927), used "taboo" occasionally in relation to Israel's Tabernacle and ceremonial laws, including Exodus 30:36, 29:37; Numbers 16:37,38; Deuteronomy 22:9, Isaiah 65:5, Ezekiel 44:19 and 46:20.