How to draw a curved line?

Question

Canvas

How to draw a line in js canvas like this?

Answer 1

A Bezier curve or, if it is a graph of some function, a large number of short straight line segments.
A similar bezier curve ( fiddle ):

var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");

ctx.lineWidth = 3;
ctx.strokeStyle = "green";
ctx.beginPath();
ctx.moveTo(4,4);
ctx.bezierCurveTo(160, 330, 160, 330, 316, 4);
ctx.stroke();