Different people?

In my years so far on this earth, I have noticed many people change due to the consumption of alcohol. I never understood it, but I have seen some of my best friends and some of the nicest kids turn into the complete opposite of their normal behavior. It is just strange as to why this happens. I had no idea what to think of it, so I looked online. I found that: 1.) the intoxicated may experience an overall improvement in mood and possible euphoria. 2.) They may become more self-confident or daring. 3.) Their attention span shortens. 4.) They may look flushed. 5.) Their judgment is not as good — they may express the first thought that comes to mind, rather than an appropriate comment for the given situation. 6.) They have trouble with fine movements, such as writing or signing their name.
After learning this information, I can certainly confirm it. For example, I saw one of my friends stumble around and bump into another person. Rather then apologize or ignore it, he screamed at the other person for no reason. The other person happened to be intoxicated as well, so a fight insued. This may seem like a stupid topic to discuss, but I just had to bring it up because I see it so often. People need to be more careful and be aware of their limit. Better yet, don't drink at all.