In mathematics, a (real) interval is a set of real numbers that contains all real numbers lying between any two numbers of the set. For example, the set of numbers x satisfying \(0 \leq x \leq 1\) is an interval which contains 0, 1, and all numbers in between. Other examples of intervals are the set of numbers such that \(0 \lt x \lt 1\), the set of all real numbers \(\mathbb{R}\), the set of nonnegative real numbers, the set of positive real numbers, the empty set, and any singleton (set of one element).
Bibliography
“Interval (Mathematics).” 2022. Wikipedia, December. https://en.wikipedia.org/w/index.php?title=Interval_(mathematics)&oldid=1128544570.