xx-axis coordinate of the upper left corner
yy-axis coordinate of the upper left corner
widthwidth of the <use> element
heightheight of the <use> element
xlink:hrefresource identifier (refers to the ID of another element) SVG 2 proposes to deprecate this and replace it with a simple href attribute


Details can be found in the W3C Recommendation for SVG as well as the new Candidate Recommendation for SVG2

Using an Icon

The <use> element is often used for reuseable icons, in collaboration with the <symbol> element. That looks like this:

    <symbol viewBox="0 0 16 16" id="icon-star">
        <path d="M16 6.216l-6.095-.02L7.98.38 6.095 6.196 0 6.215h.02l4.912 3.57-1.904 5.834h.02l4.972-3.59 4.932 3.59-1.904-5.815L16 6.215" />

And the <use> element:

    <use xlink:href="#icon-star"/>

The <use> element copies the <symbol> and displays it. You can also override the styles on the <symbol> on individual <use> elements, e.g.

    .red {
        fill: red;

    <use class="red" xlink:href="#icon-star"/>