Marijuana and alcohol have both been around for a long time. Science shows that, for the most part, marijuana isn't addictive, has fewer long-lasting side effects, and can ease people's pain. Alcohol, however, has been found to be addictive and have a number of long-lasting side effects when used in excess. In this way, marijuana can be more useful to humans than alcohol.
Marijuana is one of the most misunderstood substances in America. In a country where things with such negative effects, such as alcohol and tobacco, the world sees marijuana labeled as a drug and assumes it is worse. Having done actual research into the effects of marijuana on the brain and human body it seems to me as though marijuana has more positive effects on your body than it does negative. When you look at alcohol, obviously the same does not apply.
Marijuana has medicinal attributes that alcohol does not. Alcohol is actually more harmful to the body than marijuana. Much of the stigma behind marijuana use is that it is currently not taxed by the U.S. government. Use is mostly illegal but alcohol kills more people each year than marijuana ever has.
Marijuana and alcohol are both harmful to humans. On the surface, I don't think one is any more harmful than the other. They both affect organs in a negative way. Also, they lower a person's inhibitions. This can lead people to try activities that they wouldn't usually try. Many times this includes activities that are dangerous. However, each person is different and will be affected in different ways and to differing extents.