The real numbers, denoted by $\mathbb{R}$, are an \reftext{def:ordered-field-c54-2026b}{ordered field} that satisfies the least upper bound property in the following sense. Every nonempty subset of $\mathbb{R}$ that is bounded above has a least upper bound in $\mathbb{R}$ in the sense of \ref{def:upper-bound-supremum-c54-2026b}.