The purpose of this chapter is to introduce different numeric sets that form
the real numbers ℝ, their properties and their geometrical representation in an oriented
number line. Some specific properties are addressed, such as irreducible fractions and
divisibility.
Keywords: |, ℝ+, ℤ+, ℤ, Absolute value, Closed intervals, Half-open intervals,
Infimum and Supremum, Integer numbers, Irrational numbers, Maximum element,
Minimum element, Natural numbers, Open intervals, Properties of a real field,
Rational numbers, Real field ℝ, Triangle inequality.
