We will start with a simple line graph.
<?php
//Include the code
require_once 'phplot.php';
//Define the object
$plot = new PHPlot();
//Define some data
$example_data = array(
     array('a',3),
     array('b',5),
     array('c',7),
     array('d',8),
     array('e',2),
     array('f',6),
     array('g',7)
);
$plot->SetDataValues($example_data);
//Turn off X axis ticks and labels because they get in the way:
$plot->SetXTickLabelPos('none');
$plot->SetXTickPos('none');
//Draw it
$plot->DrawGraph();
And that's it! What we get is the following graph:

That's a great start, but now we would like to specify the width and height of the image, and add some titles.