How to get someone unconscious?

I know there are easy moves you can do to get someone unconscious during a fight. How do you do that? Is there a pressure point you can hit to make them become numb or motionless (kind of like Ty Lee in Avatar), or if you can pinch someone's shoulders or something to make them unconscious for only a little (like Sam from iCarly)? If you can tell me how, I was wondering if you could also tell me how long the effect would last, like if it would last all day, or thirty minutes, or seventy minutes or anything.