SVG noob question...

Hi there. A SVG file is not really a picture. It's a long list of XML using mathematical calculations to render an image. The result of this, is that a SVG is infinitely scalable. In fact, it stands for Scalable Vector Graphics. It doesn't lose image quality as you increase the size. There are programs out there that can try to run over a raster image and produce a SVG, but in my experience there is generally significant color and sharpness loss. So if you need a simple icon-type image with limited colors then SVG is definitely the way to go. It's also sort of cool to note that because this is all XML, it can be manipulated with CSS. You can, for example, have part of an icon disappear or blink or pretty much whatever you want it to do with enough creativity. In fact, there's a course on animating SVG here at Treehouse.

You can view it here

I might also suggest checking out the MDN documentation for SVG.

Hope this helps!

edited for additional note Yes, the quality affects the overall size of the file as it contains more data, which in turn affects the load time of the image.