To illustrate functions or to draw graphs in gerneral, it requires a coordinate system.
Cartesian coordinate system
In math we use the cartesian coordinate system.
For that we need coordinate axes, meaning two perpendicular staight lines. These are our two axes.
If only the positive values are important, a coordinate system can also look like this:
In the coordinate system, you also only draw the arrows in the positive direction.
As you can see a coordinate system is divided into four quaters, called quadrants, by the axes.
The naming is done counter-clockwise.