Trafficking Children

Trafficking Children : What does human trafficking mean exactly especially trafficking of children. Does it mean just bringing children over the border?  Are they harvesting children for their organs and their blood are they using children for sex?  How can we allow this to exist in our world? These evil people that are doing this need to be stopped. And anyone that is not willing to open their mind that this is real is just as guilty as the evil people that have done this to our innocent children.