Lifestyles of the Down and Out

I was just mentioning to my friend Nathan recently that I didn't know what those blue vials were for. You know, the one's you always see around the syringes. I knew there were filled with something necessary for drug use, but what exactly? Well, after Google-juggling the right keywords, I've eventually landed on this:

"Note: It is important to rinse the syringes and needles with water after cleaning them with bleach, so that you won't inject the bleach into your body. And how do you know when 30 seconds are up? Use a watch or a clock, or hum the song "Happy Birthday to You," all the way through, three times over."

www.hiv.va.gov/vahiv?page=ptfaq-2007-04-11

So one vial must be bleach; is the other vial something else? Heroin perhaps? Or are they the same thing, just different brands? Who knows? Help me, someone. I'm naive. Also, what does crack look like? And I know you shouldn't taste cocaine, but if you did, what would it taste like? Certainly not chicken...

...ok, I had spelled VIAL incorrectly; spell it properly, and you're more likely to make the connection to meth. But I still don't know how it all works.