As HTML emerged it's clear to see that it's most important differentiating feature is the hypertext link in the form of the anchor element. As language grew it again to see structure syntax and semantics. These all go through changes to emerge to a clean way of describing content

HTML is a declarative interpretive markup language. Declarative means that we are describing what something is not how it works. Interpreting a language requires an interpreter in this case the user agent or what we are most familiar with the web browser.

When it was formalized the first thing we would see at the top of an HTML document would be a declaration. This declaration comes from sgml and defines the document type and provides a URL where the elements attributes and other aspects of the language are outlined and defined.

After the doctype declaration we have the root element of HTML followed by the head elements the title elements any metadata which is data that's not displayed but is important to the processing and interpretation of the document. The body contains our content.

In the head elements we find such things as the title Elements which is required and helpful for orientation within a site as well as enhancing understanding about what that page content is focused on. We'll also see character set, key words, description and other items.

Once we close the head elements properly we can move on to the body. This is where our content which we want to be displayed in the browser goes and marked up accordingly such as H1-H6, paragraphs, lists, tables, and other information describing the content.

A lot more information about how the structure emerges overtime but understand that prior to CSS the concept of semantics as being meaningful to the content or presentational of the content was not an initial concern although it became one with time.

Again the idea is to have created a Content Rich document with links to other Pages or other sites that expand the information available.

The HTTP or hypertext transfer protocol now most often only seen as HTTPS which adds a layer of security is the protocol that transfers one click of a link request to the reference document. The URL would be the location address of the document we want to link with.

So far pretty easy in general to understand. There is no style and there is no presentational HTML so much at this point so browsers would display content fairly similarly and structurally in order of the content within the document.

In the open web stack another layer occurs and that is the presentation layer this is CSS. CSS can words that can be in the elements in the document in the document head as a link or imports to an external CSS file or a user Style which a usercan create and he or she might want.

We can also have what's known as an embedded style sheet which is placed in the head portion of the documents inside Style Elements and they are to control singular page needs. This is ncss known as origin. What is the origin of the rule? It's in the external stylesheet.

Some styles are inherited others are not it just depends upon the dtd in use. Do you have the same style or similar elsewhere? you may end up with a conflict meaning you must change the sort order or specificity as needed.

More to come that's a simple intro now for dinner and watch party with my brother and his Ronnie bear as is our weekend tradition. I'll stop back with the next steps as I can. Please feel free to ask questions or clarifications in this simple explanation the web.😎