What is an essential requirement for using the <canvas> element effectively?

The ability to use the element effectively is closely tied to JavaScript, as it serves as the primary means by which you can manipulate and draw on the canvas. The element itself provides a drawable region in the HTML document; however, without JavaScript, you cannot create shapes, images, or graphics within that region. JavaScript allows you to access the canvas's drawing context and issue commands to render various shapes, text, images, and even animations on the canvas.

While CSS can be applied for styling purposes, it does not contribute to the drawing or rendering of graphics within the canvas. Similarly, the element doesn't inherently require an image file to function, nor does it depend on being embedded in a table for effective use. The core functionality and flexibility of the canvas come from JavaScript, making it the essential requirement for effective use.