The answer to this [stackoverflow question](https://stackoverflow.com/questions/2142535/how-to-clear-the-canvas-for-redrawing) effectively says to retrace the steps taken to draw a rectangle:

```
fillRect

```

by doing:

```
clearRect

```

First of all when I read this answer, I thought to just draw a white box the entire width and height of the canvas.

After thinking a bit more about how the Canvas element can save, and restore and the fact it implements a `clearRect`, does this mean that simply drawing another large rectangle could eat resources, if doing something like redrawing an entire bar graph every 100ms.

Originally drawing a bar graph every 100ms drew bars on top of each other, thus not being able to see the new bars because they're being layered.

But now, drawing a white rectangle as well, means that many rectangles are getting drawn, layered and it seems that the Canvas element tracks these?

Does this mean that it is possible to effectively overload the element, or overload the browser?