They’re radically different. Things like <link rel="stylesheet">, <script> and <img> are subresources: instructions to the browser to fetch and use the specifi

They’re radically different. Things like <link rel="stylesheet">, <script> and <img> are subresources: instructions to the browser to fetch and use the specified resource, so that the page can be rendered properly. As you say, the user agent can choose to ignore these instructions (and text-mode browsers will generally ignore all three of these subresource types), but the page will probably be materially compromised, and the developer placed the subresource there with the expectation that it will be loaded. A hyperlink is a reference to another page altogether, that it’s up to the user to access if they choose to. It’s not a subresource.