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An infinite set is a collection of objects that is unlimited or endless. In mathematics, this concept is crucial for understanding concepts like the sequence of counting numbers (1, 2, 3, ...) or the number of points on a line.1

The size of infinite sets is measured by transfinite numbers, denoted by the Hebrew letter aleph (ℵ). For instance, ℵ₀ represents the size of the set of integers, which is considered "countably infinite" because its elements can be paired off with the integers. However, some infinite sets, like the real numbers, are "uncountably infinite" and are considered larger. This means not all infinities are the same size, a concept rigorously demonstrated by Georg Cantor.21

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