Claim: Documents of religious instruction have been written since the beginning of Christianity and a catechism is typically an assemblage of these smaller documents into one large compilation, making catechism itself in a question-and-answer format, and a source on which to base such catechisms.
Evidence: Documents of religious instruction have been written since the beginning of Christianity and a catechism is typically an assemblage of these smaller documents into one large compilation of Church doctrine and teachings. The Catechism itself is not in question-and-answer format. Rather, it is instead a source on which to base such catechisms (e.g. Youcat and the United States Catholic Catechism for Adults) and other expositions of Catholic doctrine, called a "major catechism."