🔗 Why does target=”_blank” have an underscore in front?

Ever wondered why you need the underscore in target="_blank" to open a link in a new tab?

Before HTML5, developers used <frameset> for SPA-like functionality, dividing the window into multiple frames, each with its own unique name. For example, the left frame might be name="sidebar", and the right frame could be name="content".

When clicking a link, the browser needed to know which frame to load the content into. That’s where the target attribute came in. Clicking a link in the sidebar, for example, would load the content in the content frame:

<a href="/pricing" target="content"></a>

Now, if you had a frame named “blank” and used <a href="/" target="blank">, the content would load in that frame. But if no such frame existed, the browser would create a new window (not a tab, as browsers didn’t support tabs at the time) and assign it the “blank” name. Clicking the same link again wouldn’t open another tab.

So why the underscore in target="_blank"?

It’s simple - developers needed a way to explicitly tell the browser to open the link in a new tab, free of frame semantics. The underscore signifies a special value rather than a frame name.

P.S. Don’t use <frameset>. It’s deprecated in HTML5.