Let's consider a code example showing what would be allowed (or not) using different levels of inheritance: 1  class BaseClass {}; void freeStandingFunction(BaseClass* b); class DerivedProtected : protected BaseClass { DerivedProtected() { freeStandingFunction(this); // Allowed } };
Definition of Horizontal Axis. Horizontal means flat or level. Horizontal axis is the x-axis on a graph. The blue number line in the figure below is the x-axis, the horizontal axis.
The vertical line is known as the y axis. It is nothing more than a measuring stick to count how far up or down a point is from the horizontal line. The horizontal line, then, is known as the x axis and measures the distance left or right from the vertical line.