Does Code Order Matter?

[PeterMurray]

I read/was told that it was a good idea to order your HTML to show the most important content first. So, on many sites I had put my global navigation div, for instance, below my main content div. Does this still apply? And does wise use of HTML 5 mean this is no longer necessary (eg use of "nav" section tag to indicate this section is about navigation).

In the same vein, how does Google know that my sidebar nav is my sidebar nav (which your site seems to say is probably given less weight than top nav), and how does it know my topnav is my top nav? Maybe a daft question, but when someone asked me yesterday I realised I didn't know!

(Phew - at last I have asked a short question!).

[Theo-NL]

I got the same question during a presentation I was giving recently and have to admit I didn't knew the answer on the spot either. Some thinking and discussing with others has given me a pretty clear picture on this though, which I will now try to pass on to you.

I don't think code order matters that much anymore. A couple years ago, when Google was crawling only a portion of a large webpage (mostly due to hardware restrictions), you'd better make sure your valuable text or links were placed in the first part of your webpage, otherwise it wouldn't get crawled at all! With Google crawling large webpage in total (if I recall some quote from Matt Cutts correctly he stated that they now index webpages over several MBs in size, as long as they contain enough valuable information).

With Google advancing their detection of the 'visual location' where text and links are placed on a webpage (see #5 on http://www.seomoz.org/blog/10-illustrations-on-search-engines-valuation-of-links), source code ordering will most likely have dropped in value as well. Using CSS styling, we can now order our source code pretty much at will anyway, which has changed it from a valid signal to a 'SEO trick' (just like adding a suffix to the URL has, see http://www.finishjoomla.com/blog/5/does-adding-a-suffix-to-my-urls-affect-my-seo/).

By 'viewing' (and perhaps manually categorizing or using machine learning http://en.wikipedia.org/wiki/Machine_learning) webpages Google will notice patterns in webpage source code. For example: 'that div containing a large amount of links, usually placed in an ul-li, often containing links to 'home' and 'contact' will most likely be your menu. Just like 'that div containing more text than any other div, often starting with a H1 or H2 tag, containing the most images and ending with a call-to-action' link will most likely be your page content area. Thus, Google doesn't 'know' whether a certain part of your source code is your menu, your sidebar or your page content, it deducts it by looking at common patterns.

(lol, my answer is more than three times as long as your short question!)

[PeterMurray]

Thank you - and very happy to receive a longer answer than my question!

That certainly answers my basic question, and I really appreciate it.

What do you think about the more "semantic" tags of HTML5 - such as the "nav"? Surely it's a good idea to use them to help Google (and later web developers) on their way with understanding the structure of the content?

And, a related question, can and does Google read CSS files to determine structure too? It's not mentioned on the blog post you pointed me to (and thanks for pointing me to it - a very helpful article in all sorts of ways which I hadn't read.)

[Theo-NL]

Perhaps HTML5 tags are used as one of the signals in determining which piece of source code is what. Seeing how easily one could manipulate these tags, I don't think it'll be a strong signal though. Of course it can be a good guidance for future web developers to identify pieces of source code!

Google is able to read CSS files (for example to determine if a link is hidden), but I don't think it will parse these files and apply them to the webpage to determine the visual layout of it. I think it would require a great amount of processing power (and time) to actually render a webpage, rather than sort out the pieces based on the source code like I described in my answer above.

Glad I could help!