Rational number $p/q$ can be represented in their decimal form. On division of $p$ by $q$ , two things happens :
a) Either the reminder becomes zero .
or
b) Remainder never becomes zero and we get a repeating string of remainders.

Case 1: The remainder becomes zero
Example of $7/8$
We call decimal expansion of such numbers terminating.

Case:2 The remainder never becomes zero.
In example of 10/3 and 1/7 , the remainders repeats after a certain stage forcing the decimal expansion to go on for ever. In other words , we have a repeating block of digits in the quotient.
We say that this expansion is non-terminating recurring.

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