Catechesis is basic Christian religious education of children and adults, often from a catechism book. It started as education of converts to Christianity, but as the religion became institutionalized, catechesis was used for education of members who had been baptized as infants. As defined in the Catechism of the Catholic Church, paragraph 5 :Catechesis is an education in the faith of children, young people and adults which includes especially the teaching of Christian doctrine imparted, generally speaking, in an organic and systematic way, with a view to initiating the hearers into the fullness of Christian life.

In secular usage, religious education is the teaching of a particular religion and its varied aspects: its beliefs, doctrines, rituals, customs, rites, and personal roles. In Western and secular culture, religious education implies a type of education which is largely separate from academia, and which (generally) regards religious belief as a fundamental tenet and operating modality, as well as a prerequisite for attendance.