GQ: Why would I want to put information on my web page that is not visible to the typical user?

I would want to put in information not visible to the typical user because the coding includes information many users would not need to know. Metadata is a description that gives search engines commands on how to show certain things. They are important and needed because they are not visible in the web page but they give important information like the language. Metadata is used by browsers and changes how the webpage is viewed. Many tags, such as tags about style, formatting, and metadata are physically on the web page. However, viewers do not need to see the actual words "metadata", it's not necessary because they can see how the browser shows it. For example, the metadata viewport can change how the web page is viewed from a mobile device but there's no actual writing the user will need to see. For the tag "span" if I wanted to color a certain word or phrase, I could either use the color name, hex code, or rgb code-things that may not be known to the typical user but if I used those, the color would show up in my web page. The viewer doesn't need to know the actual color name, hex code, or the intensity of red, green and blue in the color which is the rgb value. These tags are used to make the web page stand out so they don't look bland but the information I put on my web page does not need to be shown because the coding and the way it's shown on the web page is different.