The Faith, A Popular Guide Based on The Catechism of the Catholic Church, by John A. Hardon, S.J. has this:
- What are the two kinds of evil in the world?
They are moral and physical evil.
(310-311)
- What is moral evil?
Moral evil is sin. It is evil because it is contrary to the will of God. It is moral evil because it is caused by a free created will acting against the will of God. He does not want moral evil as an end or as a means.
- What is physical evil?
Physical evil is the privation of a natural physical good. It is evil because something is lacking in what it should be. It is physical because the lack or privation is in the nature (physis in Greek) of a thing. The privation may be material, like the size or strength of a body; or it may be spiritual, like ignorance in the mind or courage in the will. When this privation is consciously experienced, it is painful suffering which may also be called a physical evil.
(310)
- Why is there physical evil?
There is physical evil because God willed that there be limitations in the world He created. These limitations provide us with the opportunity to develop the world in which we live. Yet, as the Second Vatican Council reminds us, such “earthy progress #133; is of vital concern to the Kingdom of God, insofar as it can contribute to the better ordering of human society” (Gaudium et spes, 39).
therealpresence.org/archives/Catechism/Catechism_010.htm