There is a difference between physical addiction and mental addiction. Drugs such as heroin, cocaine, and even alcohol and tobacco (and caffeine, to an extent) can cause physical dependency. This means that when you are off the drug, you will feel down and perhaps experience pain and other symptoms that can only be treated by using more of the drug. This is not the case with cannabis. However, you can get mentally addicted. This just means you like the drug so much it is hard to stop. Mental addiction does not only apply to drugs. TV, Soda, Video Games, and other hobbies/activities/food etc. can all be mentally addicting. I am for legalization. Just do it in moderation.
Marijuana, like any chemical substance, can be addicting. People may not become physically dependent upon marijuana, but they can become psychologically dependent upon it and use it to cope with stress in their daily lives. It is important to be aware of the power of mind altering substances and the ways in which we may use them to escape reality.
Marijuana can be addictive, based on how it is used and what kind of health problems the person using it is trying to address. The pharmaceuticals we take to treat health problems are health forming, just based on the benefits they give us. Marijuana can work the same way in the fact that you may form a dependence on it to feel better.
Marijuana has been found not to be physically addictive. Some may develop a dependance on it, while others can take it or leave it. Like anything, it can be used as a crutch. Chronic users who quit may get unpleasant side effects like being cranky or stressed out because they aren't used to dealing with life sober, but that will subside withing a few days to a week.
Marijuana has not been found to be particularly addictive, however dependence on its use can be the result of an underlying health problem that has been left unaddressed. This could leave the user at risk of becoming dependent on more addictive drugs to deal with increasingly severe symptoms of deteriorating health.