How is data measured in my cell phone plan?

I just renewed my contract with Verizon, and got a minor data plan. I have never had this before, and am a bit confused. It says my monthly data limit is 23 MB. How is this measured, what kinds of things use up my available MB?How is data measured in my cell phone plan?
WHEN YOU GO ONLINE ON YOUR PHONE OR COMPUTER IT DOWNLOAD INFORMATION THIS MEASURED IN WHAT IS CALL BYTES 23mb STANDS FOR MEGA BYTES WHEN YOU TEXT IF ALSO USES BYTES OF INFORMATION LIKE A FEW Bk's KILO BYTES WHICH KILO IS SMALLER THEN A MEGA BYTE I WOULD GO WITH UNLIMITED IF YOU DO ALOT OF INTERNET ON THE PHONE BUT CAN BE SLOW. OR DO ALOT OF TEXTINGHow is data measured in my cell phone plan?
check this video for ur answer http://www.videojug.com/expertanswer/mobile-internet-basics/how-are-data-transmission-rates-measured