I second Jacques link to TTE's DCC for Beginners. You can either read it online or download it onto your computer. Good place to start and should answer a number of your questions.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Try this link for a start
http://www.tonystrains.com/tonystips/dccprimer/index.htm
Jack W.
explain a DCC to me someone