how did friendship begin?

This is a very intriguing and interesting question that many must have stumble and broad upon, how exactly made me like this guy and let me hate the other? Sometimes I find myself liking someone immediately right after we talked, and find the opposite result with someone else  I also encountered someone who dislikes and is rude to me right when me met, without getting to know me, but nice to some other equally unfamiliar people. So what exactly sparts friendship? I think that common interest and personality similarities differences(depending on the person) might spark friendship. I find myself immediately going into a deep conversation and also felt confortable chatting to a random stranger about video games or star wars( it may not be the best way to make friends but most of my friend made way are quite nice and fun.). Some people may prefer different or similarities of their personality as well. A rude guy might be friends with a understandable and nice guy easily dismiss the insult and sees the best in people. Two people with similar personality might also find themselves more relatable and can easily share and talk about things.