What if I stripped all HTML tags from my content? Except maybe <br> tags for newlines. The site might not look too nice but from a search engine's perspective crawling the site would it matter?
<html>
<head><title>No Tags</title></head>
<body>
<!-- Entire site content without HTML tags-->
</body>
</html>
They would deal with it. The problem you would have is that formatting almost wholly goes out the window and any signaling with it. Search engines look to the tags for clues as to what the topic is, what the author thinks is important, and how to place the page in the SERPs. Header tags, paragraphs, and the like, are important tools to communicate your ideas just as much as the written word. For example, search engines look to the header tags to know what the topic of the following paragraphs are. Each term used in a tag is weighted accordingly and this helps to match the page to a search intent.
This answer gives you some idea of how this works: Improve Google ranking for general vs. specific keywords There is much more to it than that of course, but it is a good jumping off point.
Otherwise the text would be taken as a single paragraph with breaks in between. This is standard formatting for text to HTML though some parsers would make each paragraph on it's own. It is hard to tell which method applies. There are some plain text pages in Google for example, but it is not recommended. In this case, each succeeding paragraph would have less weight for the terms used and there would be no boost for terms due to the lack of signalling with tags. The page would perform, but not likely well. You see, search is a competitive thing these days. Every piece of content has to compete or it will get lost in the huge mass of data available. Any plain text page, unless highly relevant to a search query, would not be seen. Not any more.
Just putting this out there if anyone is wondering since it's along the same lines. Google does not penalize you if your HTML is broken on the page. If that was the case, a huge number of sites on the Internet would be penalized.
Matt Cutts said:
Google does not penalize you if you have invalid HTML
This doesn't mean you shouldn't give your HTML a look and see if there's any missing <div> tags or if you forgot to close your <h1>.
Just wanted to throw this little tidbit of information out there, somebody might find this useful.
I am taking your example for the explanation. Head and Title tags helps Google to identify your site. When Google bots(crawler) crawl your site they look for information. Header and title tags are the indicator of your website subject. Content is generally lie within HTML body. Therefore search engine look into body section for your website content. Therefore you can understand how important HTML sections are. You may still prefer the No HTML format. In that case search engine will have problem to understand your site and consequently your website will never be visible on top search results. Understand how Google crawl your website.
