... ... ... ... ... ... yeah. you got to be kidding me.

the carb is covered with your finger while the weed is burning. when you release the carb hole, it causes air to flow through the pipe. It's used to "clear" the pipe; that is, when your thumb is covering the carb, smoke builds up within the pipe. When you release the carb, the smoke no longer builds up inside the pipe , because there is air coming in through the carb; all the smoke that has built up inside the pipe is now no longer trapped in the pipe; it goes into your lungs, and happy feelings are produced

the carb allows for fatter hits.

you said you're new to toking. how new? you sound hell of novice to me. but hey everyone has got to start someplace. enjoy your new hobby. i hope you like being broke as shit hahaha