<P> The division 3 ÷ 2 on the real number line </P> <P> The section of the number line between two numbers is called an interval . If the section includes both numbers it is said to be a closed interval, while if it excludes both numbers it is called an open interval . If it includes one of the numbers but not the other one, it is called a half - open interval . </P> <P> All the points extending forever in one direction from a particular point are together known as a ray . If the ray includes the particular point, it is a closed ray; otherwise it is an open ray . </P> <P> On the number line, the distance between two points is the unit length if and only if the difference of the represented numbers equals 1 . Other choices are possible . </P>

How to represent different types of numbers on a number line