What is Demand Draft (DD) number

I have to mention dd number in some where but for me it was diificult to found even tho after google a half hour "what is dd number"

 So for help of other i'm posting here for dd number queries

1)just check your lower bottom of demand draft (DD)
   there is long number is written there

2)Only the first six digit are useful and its your dd number

 Sample dd image of bank of baroda

 Here red circled number is a dd number
 Remember first six digit is dd number

Next nine digit number after dd number is MICR NO. in which
out of which 9 digit
first 3 are for disttrict
next 3 are for city
next 3 are for branch