In the past, children were raised mostly by their biological parents. In the rare case that they were not, they had either to survive on the streets or live in orphanages. However, times have changed, and today children can be raised in single-parent families, by grandparents, foster parents, stepparents, or other parenting figure all this is due to the procedure of adoption, which has become common worldwide. However, the occurrence of adoption has a number of features which distinguish it from a simple residence of a child in a family.