javascript.js - $.plot is not a function

[MrBitLit]

``// Set up the control widget

	var updateInterval = 50;

	var plot = $.plot("#debugChart", [setData()], {
			series: {
					shadowSize: 1 // Drawing is faster without shadows
			},
			yaxis: {
					min: 0,
					max: 600
			},
			xaxis: {
					show: false
			}
	});

Can someone explain me how to fix the error, that would be really nice!