Puberty is the time of change when young people begin to develop the outward signs of becoming an adult and when they become able to reproduce (have a baby). Puberty starts when hormones from part of the brain (pituitary gland) act on the ovaries or testes to begin sexual changes in both boys and girls.
As we are all different we can go through puberty at different times and at different rates. puberty brings both physical and emotional changes. Some people seem to go through all the changes easily and others may have a few problems.