Where can I find a clear example of plotting graphs in php or js?

Question

PHP

Friends, I can’t find anywhere a simple easy example of creating a line graph "let's say site visits"
For those who can help, send some information on how to generate a simple site visit graph
in php GD or javascript SVG
The question has a big bias on the principle of creating a graph, what rules are needed observe to generate it?
Please do not offer ready-made solutions like phpChartFrameworkBundle2017_packRepackPro which, let's say, weighs 90 megabytes. Here's a simple example to get the point across.

Answer 1

for example, we receive data from the server in the form
[{day: 1, visitors: 10},{day: 2, visitors: 20},{day: 3, visitors: 15}]
and in js we draw an svg line with coordinates
x - day
y - visits
what other rules then? To work with svg in js, I personally use svgjs.com

Answer 2

https://www.highcharts.com/demo