Basically, addiction of something is a condition of being addicted to some particular substance, thing or some times activity. Addiction creates a condition due to which people do not have control over what he/she is doing, taking or using. Sometimes, addiction may reach a point at which it is became harmful for that particular person and in worse case scenario more harmful for related person to him/her. Addiction could be for many things but the most harmful addictive substances are alcohol, cocaine, nicotine or sometimes physical activity like gambling. Initially, all these kinds of substances and activities could be pleasurable but the continued use of these things can become compulsive and interfering in the normal life responsibilities. Responsibilities like work relationships, health etc. effects a lot. Most of the time, users may not be aware or know that their behavior is slowly slowly becoming out of control and causing problems and creating difficulties for themselves and specially for others.
Probably, the word addiction is used in several different ways and also categorize in few categories. One category is describes physical addiction which is a biological state in which the body adapts to the presence of a drug so that drug no longer has the same effect; this is known as tolerance. Because of allowance, there is a biological reaction when the drug addict backs out from its use.

Another category of physical addiction is the phenomenon of overreaction by the brain to drugs or sometimes, to cues associated with the drugs. Like an alcoholic walking into a bar, for instance, will feel an extra pull to have a drink because of these cues.

Marijuana rehab centers conclude some facts about why some drug users become addicted, while others will not?
They said that there are many factors which are different in people like if the person belongs to such kind of family history of which is also related to addiction then this kind of situation make huge difference with normal user or whose past related to addiction.

Few people also phase such kind of incidence which drag them in the valley of loneliness or being different from others. Such as some kind of abuse, neglect or other traumatic experience in childhood. Treatment centers in Chicago which are famous in treating drug addicts believe that some kind of mental disorders like depression, guilt, loneliness or anxiety also promotes user towards addiction.