graph paper

US /ˈɡræf ˌpeɪ.pər/
UK /ˈɡræf ˌpeɪ.pər/
"graph paper" picture
1.

paper printed with a network of lines, typically in squares, used for plotting graphs or drawing diagrams.

:
We used graph paper to plot the data points for our experiment.
The architect sketched the initial design on graph paper.