a straight line
A discrete graph.
The advantage is being given a straight answer, but in a graph it doesn't give you a straight answer, because there is a possibility of data being in between the plotted points.
line plot
Line Plot
nonlinear graph.
nonlinear graph
a line of best fit
a line of best fit
a line of best fit
a line of best fit
There is no specific name. It could be a non-linear graph, or a scatter graph.
linear graph
The definition is any chart where one or more points lie off the straight line joining the other points.
a straight line
a straight line
A Linear graph