Of course, we all know that Web has become more and more an application platform than an information medium. Such argument could holds true, evidentially, is by the invention of the element <canvas>: before canvas, every HTML tag was invented to host some type of content or metadata; Javascript, or other client-side scripts, heavy or lightweight, rich or sample, do nothing more than manipulating those data (and replace them with new data fetched by XMLHttpRequest or JSON-P).

<canvas>, however, is the only element doesn’t come with content. Without script, canvas is nothing more than a blank block space. It is, indeed, a canvas for Javascript to “paint” its computation result. You cannot specify any content with element attribute; without script the canvas itself doesn’t make any sense.

Years from now, when people talk about the history of advancement of Web technologies, I believed notions like this would eventually reveal itself; just like what happened when we talked about the day when <img> is invented.

Food for thought.