Puberty is a relatively short, 1 to 3 year, period when the growing child undergoes changes which result in sexual maturity, usually around age 12 years. Adolescence is a considerably longer period, perhaps 8 to 10 years, which begins in late childhood, and during which the child slowly matures physically and psychologically from a child to a young adult. It is roughly equivalent to the teenage years in many societies.

* puberty =sexual maturity * adolescence =age of puberty

http://hes.ucfsd.org/gclaypo/repro/pubado01.html