Definition of period of a decimal representation of a number I need to define the period of a decimal representation of a number!!

Thanks in advance!!
It's just how many digits in the repeated part i.e. 1.23123123... has period 3
PERIOD IN DECIMAL NUMBERS-
Period means that in recurring or in
terminating decimal the repeating decimal is known as period 
Example-
     7.9999........ continuously goes
So, 
Here 9 is period because only 9 repeat continuously.