Tags that have an opening and closing tag (anchors, span, divs, etc.) do not need / "> because / is in the closing tag.
It is assumed that those that stand alone (br, hr, img, etc.) now have / ">.
As far as I understand, this is not necessary, but it was introduced into the game for HTML5 for the sake of consistency with XML and XHTML.
I read that before / "> you need to put a space so as not to confuse old browsers.
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