A number line can be defined as a straight line with numbers placed at equal intervals. A number line can be extended infinitely in any direction and is usually represented horizontally. It can be used to represent both positive and negative integers. Every number on the number line has an absolute value, which simply means how far that number is from zero. The section of the number line between two numbers is called an interval. The distance between a number's place on the number line and 0 is called the number's absolute value..
