What is ADHD or attention deficit hyperactivity ?

This is a behavior related problem both in children and adults which can turn their life into heck. Children get this disorder mostly from adults, therefore there is a serious need to keep behavior balanced.

Attention deficit hyperactivity disorder is a disorder related to the children or adults. In this this disorder children or adults fail to focus on anything for longer duration, fail to remain attentive, is hyperactive, or acts impulsively. Though the cause of this disorder is yet to be discovered, however it can be corrected with proper medication, timely counselling.

It is a type of mental disorder.

ADHD is mental disorder in which the person has either lack of attention or impulsiveness or both.

ADHD is problem with inattentiveness, over-activity, impulsive behavior, or a combination of all these in young children. It is still not clear as to what causes this, but it is seen more in boys than in girls and is believed to run in families. It may also be linked to developmental or behavioral problem. It is not easy to diagnose a child of having ADHD based only on symptoms but a series of tests are required to be run before concluding. Treatment includes combination of some therapies and drugs which usually are psychostimulants.

See link for more information about ADHD:
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002518/

This is a behavioral problem and is related to attention deficit.