What is a line that represents a set of all real numbers in order?

A line that represents a set of all real numbers is often depicted as a number line, which extends infinitely in both the positive and negative directions. Each point on the line corresponds to a unique real number, and the line is continuous without any gaps or breaks. This visualization helps to illustrate the density of real numbers, meaning between any two distinct real numbers, there are infinitely many others. The line can be labeled with positive numbers to the right of zero and negative numbers to the left.