Every fraction has a decimal expansion that either terminates or eventually repeats.
Examples
- 1/2 = 0.5 — terminates.
- 1/3 = 0.333… — repeats with period 1.
- 1/7 = 0.142857142857… — repeats with period 6.
Irrational numbers like π or √2 don't repeat — that's what makes them irrational.