Re: Is it urine or something else?
precum is pre... like storm said it helps clear your penis of acid that urine leaves, it happens when your aroused because it is preparing for sex, girls get the same thing
cum is what comes out when you orgasm(done by masturbation, its basically the end of sex for a male), its basically sperm if your body is making it (sometimes you can "shoot blanks" which means you arn't producing enough sperm or its all dead, usually from old age or a disorder)
all those? ill answer if you can give some more details, or you may want a new thread