HTML5 best practices; section/header/aside/article elements [closed]

Solution 1:

Actually, you are quite right when it comes to header/footer. Here is some basic information on how each of the major HTML5 tags can/should be used (I suggest reading the full source linked at the bottom):

section – Used for grouping together thematically-related content. Sounds like a div element, but it’s not. The div has no semantic meaning. Before replacing all your div’s with section elements, always ask yourself: “Is all of the content related?”

aside – Used for tangentially related content. Just because some content appears to the left or right of the main content isn’t enough reason to use the aside element. Ask yourself if the content within the aside can be removed without reducing the meaning of the main content. Pullquotes are an example of tangentially related content.

header – There is a crucial difference between the header element and the general accepted usage of header (or masthead). There’s usually only one header or ‘masthead’ in a page. In HTML5 you can have as many as you want. The spec defines it as “a group of introductory or navigational aids”. You can use a header in any section on your site. In fact, you probably should use a header within most of your sections. The spec describes the section element as “a thematic grouping of content, typically with a heading.”

nav – Intended for major navigation information. A group of links grouped together isn’t enough reason to use the nav element. Site-wide navigation, on the other hand belongs in a nav element.

footer – Sounds like its a description of the position, but its not. Footer elements contain informations about its containing element: who wrote it, copyright, links to related content, etc. Whereas we usually have one footer for an entire document, HTML5 allows us to also have footer within sections.

Source: https://clzd.me/html5-section-aside-header-nav-footer-elements-not-as-obvious-as-they-sound/

Additionally, here's a description on article, not found in the source above:

article – Used for element that specifies independent, self-contained content. An article should make sense on its own. Before replacing all your div’s with article elements, always ask yourself: “Is it possible to read it independently from the rest of the web site?”

Solution 2:

Unfortunately the answers given so far (including the most voted) are either "just" common sense, plain wrong or confusing at best. None of crucial keywords¹ pop up!

I wrote 3 answers:

This explanation (start here).
Concrete answers to OP’s questions.
Improved detailed HTML.

To understand the role of the html elements discussed here you have to know that some of them section the document. Each and every html document can be sectioned according to the HTML5 outline algorithm for the purpose of creating an outline—⁠or⁠—table of contents (TOC). The outline is not generally visible (these days), but authors should use html in such a way that the resulting outline reflects their intentions.

You can create sections with exactly these elements and nothing else:

creating (explicit) subsections
- <section> sections
- <article> sections
- <nav> sections
- <aside> sections
creating sibling sections or subsections
- sections of unspecified type with <h*>^² (not all do this, see below)
to level up close the current explicit (sub)section

Sections can be named:

<h*> created sections name themselves
<section|article|nav|aside> sections will be named by the first <h*> if there is one
- these <h*> are the only ones which don’t create sections themselves

There is one more thing to sections: the following contexts (i.e. elements) create "outline boundaries". Whatever sections they contain is private to them:

the document itself with <body>
table cells with <td>
<blockquote>
<details>, <dialog>, <fieldset>, and <figure>
nothing else

title

example HTML <body> <h3>if you want siblings at top level...</h3> <h3>...you have to use untyped sections with <h*>...</h3> <article> <h1>...as any other section will descent</h1> </article> <nav> <ul> <li><a href=...>...</a></li> </ul> </nav> </body> has this outline 1. if you want siblings at top level... 2. ...you have to use untyped sections with <h*>... 2.1. ...as any other section will descent 2.2. (unnamed navigation)

This raises two questions:

What is the difference between <article> and <section>?

both can:
- be nested in each other
- take a different notion in a different context or nesting level
<section>s are like book chapters
- they usually have siblings (maybe in a different document?)
- together they have something in common, like chapters in a book
one author, one <article>, at least on the lowest level
- standard example: a single blog comment
- a blog entry itself is also a good example
- a blog entry <article> and its comment <article>s could also be wrapped with an <article>
- it’s some "complete" thing, not a part in a series of similar
<section>s in an <article> are like chapters in a book
<article>s in a <section> are like poems in a volume (within a series)

How do <header>, <footer> and <main> fit in?

they have zero influence on sectioning
<header> and <footer>
- they allow you to mark zones of each and every section
- even within a section you can have them several times
- to differentiate from the main part in this section
- limited only by the author’s taste
- <header>
  - may mark the title/name of this section
  - may contain a logo for this section
  - has no need to be at the top or upper part of the section
- <footer>
  - may mark the credits/author of this section
  - can come at the top of the section
  - can even be above a <header>
<main>
- only allowed once
- marks the main part of the top level section (i.e. the document, <body> that is)
- subsections themselves have no markup for their main part
- <main> can even “hide” in some subsections of the document, while document’s <header> and <footer> can’t (that markup would mark header/footer of that subsection then)
  - but it is not allowed in <article> sections³
- helps to distinguish “the real thing” from document’s non-header, non-footer, non-main content, if that makes sense in your case...

^{¹ to mind comes: outline, algorithm, implicit sectioning}
^{² I use <h*> as shorthand for <h1>, <h2>, <h3>, <h4>, <h5> and <h6>}
^{³ neither is <main> allowed in <aside> or <nav>, but that is of no surprise. – In effect: <main> can only hide in (nested) descending <section> sections or appear at top level, namely <body>}

Solution 3:

The div elements can be replaced with the new elements: header, nav, section, article, aside, and footer.

The markup for that document could look like the following:

<body>
     <header>...</header>
     <nav>...</nav>
     <article>
          <section>
               ...
          </section>
     </article>
     <aside>...</aside>
     <footer>...</footer>
</body>

You may find more information in this article on A List Apart.

Solution 4:

I'd suggest reading the W3 wiki page about structuring HTML5:

<header> Used to contain the header content of a site. <footer> Contains the footer content of a site. <nav> Contains the navigation menu, or other navigation functionality for the page.

<article> Contains a standalone piece of content that would make
sense if syndicated as an RSS item, for example a news item.

<section> Used to either group different articles into different
purposes or subjects, or to define the different sections of a single article.

<aside> Defines a block of content that is related to the main content around it, but not central to the flow of it.

They include an image that I've cleaned up here:

html5

In code, this looks like so:
<body>
  <header></header>    
  <nav></nav>    
  <section id="sidebar"></section>    
  <section id="content"></section>    
  <aside></aside>    
  <footer></footer>
</body>
Let's explore some of the HTML5 elements in more detail.

<section>

The <section> element is for containing distinct different areas of functionality or subjects area, or breaking an article or story up into different sections. So in this case: "sidebar1" contains various useful links that will persist on every page of the site, such as "subscribe to RSS" and "Buy music from store". "main" contains the main content of this page, which is blog posts. On other pages of the site, this content will change. It is a fairly generic element, but still has way more semantic meaning than the plain old <div>.

<article>

<article> is related to <section>, but is distinctly different. Whereas <section> is for grouping distinct sections of content or functionality, <article> is for containing related individual standalone pieces of content, such as individual blog posts, videos, images or news items. Think of it this way - if you have a number of items of content, each of which would be suitable for reading on their own, and would make sense to syndicate as separate items in an RSS feed, then <article> is suitable for marking them up. In our example, <section id="main"> contains blog entries. Each blog entry would be suitable for syndicating as an item in an RSS feed, and would make sense when read on its own, out of context, therefore <article> is perfect for them:
<section id="main">
    <article></article>        
    <article></article>        
    <article></article>
</section>
Simple huh? Be aware though that you can also nest sections inside articles, where it makes sense to do so. For example, if each one of these blog posts has a consistent structure of distinct sections, then you could put sections inside your articles as well. It could look something like this:
<article>
  <section id="introduction"></section>      
  <section id="content"></section>
  <section id="summary"></section>
</article>
<header> and <footer>

as we already mentioned above, the purpose of the <header> and <footer> elements is to wrap header and footer content, respectively. In our particular example the <header> element contains a logo image, and the <footer> element contains a copyright notice, but you could add more elaborate content if you wished. Also note that you can have more than one header and footer on each page - as well as the top level header and footer we have just discussed, you could also have a <header> and <footer> element nested inside each <article>, in which case they would just apply to that particular article. Adding to our above example:
<article>
  <header></header>    
  <section id="introduction"></section>      
  <section id="content"></section>      
  <section id="summary"></section>      
  <footer></footer>
</article>
<nav>

The <nav> element is for marking up the navigation links or other constructs (eg a search form) that will take you to different pages of the current site, or different areas of the current page. Other links, such as sponsored links, do not count. You can of course include headings and other structuring elements inside the <nav>, but it's not compulsory.

<aside>

you may have noticed that we used an <aside> element to markup the 2nd sidebar: the one containing latest gigs and contact details. This is perfectly appropriate, as <aside> is for marking up pieces of information that are related to the main flow, but don't fit in to it directly. And the main content in this case is all about the band! Other good choices for an <aside> would be information about the author of the blog post(s), a band biography, or a band discography with links to buy their albums.

Where does that leave <div>?

So, with all these great new elements to use on our pages, the days of the humble <div> are numbered, surely? NO. In fact, the <div> still has a perfectly valid use. You should use it when there is no other more suitable element available for grouping an area of content, which will often be when you are purely using an element to group content together for styling/visual purposes. A common example is using a <div> to wrap all of the content on the page, and then using CSS to centre all the content in the browser window, or apply a specific background image to the whole content.

Solution 5:

[explanations in my “main answer”]

line 7. section around the whole website? Or only a div?

Neither. For styling: use the <body>, it’s already there. For sectioning/semantics: as detailed in my example HTML its effect is contrary to usefulness. Extra wrappers to already wrapped content is no improvement, but noise.

line 8. Each section start with a header?

No, it is the author’s choice where to put content typically summarized as “header”. And if that header-content is clearly recognizable without extra marking, it may perfectly stay without <header>. This is also the author’s choice.

line 23. Is this div right? or must this be a section?

The <div> is probably wrong. It depends on the intentions: is it for styling only it could be right. If it’s for semantic purposes it is wrong: it should be an <article> instead as shown in my other answer. <article> is also right if it is for both styling and sectioning combined.

<section> looks wrong here, as there are no similar sections before or after this one, like chapters in a book. (This is the purpose of <section>).

line 24. Split left/right column with a div.

No. Why?

line 25. Right place for the article tag?

Yes, makes sense.

line 26. Is it required to put your h1-tag in the header-tag?

No. A lone <h*> element probably never needs to go in a <header> (but it can if you want to) as it is already clear that it’s the heading of what is about to come. – It would make sense if that <header> also encompassed a tagline (marked with <p>), for example.

line 43. The content is not related to the main article, so I decided this is a section and not an aside.

It is a misunderstanding that an <aside> has to be “tangentially related” to the content around. The point is: use an <aside> if the content is only “tangentially related” or not at all!

Nevertheless, apart from <aside> being a decent choice, <article> might still be better than a <section> as “hot items” and “new items” are not to be read like two chapters in a book. You can perfectly go for one of them and not the other like an alternative sorting of something, not like two parts of a whole.

line 44. H2 without header

Is great.

line 53. section without header

Well, there is no <header>, but the <h2>-heading leaves pretty clear which part in this section is the header.

line 63. Div with all (non-related) news items

<article> or <aside> might be better.

line 64. header with h2

Discussed already.

line 65. Hmm, div or section? Or remove this div and only use the article-tag

Exactly! Remove the <div>.

line 105. Footer :-)

Very reasonable.