What is this line referred as in a chart?

1. What is the line called in a chart?
2. What does the line represent on a graph?

What is the line called in a chart?

Axis - One of the lines that is used to form a graph. There is the horizontal x-axis and the vertical y-axis in a two dimensional graph.

What does the line represent on a graph?

The graph represents quantitative data between two changing variables with a line or curve that joins a series of successive data points. Linear graphs compare these two variables in a vertical axis and a horizontal axis.