Child pornography and Porn

Child pornography noun - The illegal use of children in pornographic pictures or films.

Porn and child pornography are semantically related. In some cases you can use "Porn" instead a noun phrase "Child pornography".

Porn noun - Creative activity (writing or pictures or films etc.) of no literary or artistic value other than to stimulate sexual desire.

Child pornography and porn are semantically related. Sometimes you can replace phrase "Child pornography" with "Porn", this terms are similar.