A round-off error is the difference between the calculated approximation of a number and its exact mathematical value. Numerical analysis specifically tries to estimate it when using approximation equations and/or algorithms.
Example Usage of Rounding
excusememister: @JasonSinger Thank you, I shall get started asap. This is a great thing you're Rounding up here. ♥
Rogcar2: ...Rounding third
danielguntrip: @hello_charlotte are you Rounding up old people?