The horizontal axis is usually called the x-axis. The vertical axis is usually called the y-axis.

Which side is the x-axis?

The x-axis is horizontal, and the y-axis is vertical. One way to remember which axis is which is 'x is a cross so the.

How do you remember the X and y-axis?

Reminder: the x-axis really runs left and right, and the y-axis runs up and down. Notice the arrows at the ends of the blue and purple lines? Those indicate the lines go on forever.