|ten||decimal, or denary|
|twelve||duodenary, or duodecimal|
But what's twelve in base twelve? 1012 of course! It follows exactly the same mechanism of returning the column to zero and incrementing the next one along. So 10012 is twelve times twelve (one hundred and forty four).
Recall the powers from bases:
The important thing to remember is that these series of digits are just a way of writing down a particular quantity. The quantity "thirty six" is still the same number of things whether it's 3012 or 3610. The base of the numbering system is an agreed on standard and the lens and language with which we see and express numbers.
Let's look at some basic arithmetic in base twelve...