I already explained why SEO and web usability go hand in hand. Let’s see some example where this happens. You will quickly realize like every big on-site SEO element is also, mainly, sometimes solely, a usability element.
Considered the most important single SEO tag in a page, the title tag is indeed very important.
How a title tag should be written to be good for SEO? It should be unique, short, meaningful. And when you have a title good for SEO, what else you have? A title good for users. Think of a SERP, where the title is shown as the biggest part of the snippet. If the title is unique, short and meaningful, it will be able to tell the users immediately what the page is about.
By the way, the SERP is also a perfect point of contact between SEO and usability.
But even in a different context, far from a search engine, a title is still very useful for a user. Think of the tabs in your browser, think how it is when you have 5 tabs open. How do you know what each tab is about? Just read the tab. It’s in fact showing the title tag.
Historically, search engines proved to have troubles to clearly understand URLs full of parameters (you know, those URLs full of ? = and &…). So, making these dynamic URLs static was a good idea from a SEO point of view. Transforming a URL from something like /?id=1&cat=2&tag=3 to /1/2/3 was such a big improvement for SE and users that it was a no-brainer. But adding keywords to the URL was even better, because a URL is still supposed to be seen by the users somewhere (and SEOs found another thing to stuff with keywords, woohoo!).
Truth is, for the search engines, URLs are friendly once they can be processed and understood correctly: when they are static. Adding keywords was believed to be an advantage from an SEO point of view, mainly because of this common misconception that keywords must be everywhere. Nonetheless, keywords in the URLs are still a good thing to use (as long as the URL doesn’t become too long), if URL is built the right way. A good URL is static, unique, short, meaningful, consistent and follow a hierarchical structure.
The anchor text has been so much abused by SEOs that it’s now one of the first signals that can trigger a Penguin penalty. But why Google decided it was worth to consider the anchor text of a link? Because an anchor text says (or, at least, should!) what the destination page is about. It says that to the search engine like it says that to the user.
Imagine you are browsing the web. Maybe you are reading an article. At a certain point, in the page, you see a link you want to follow. You click on it and… not found! User experience ruined before it even started…
Or imagine that, when you click the link, you get redirected to the homepage. Would you feel lost? I know I would!
But user experience can be preserved, if resources are moved from a URL to another.
What is the correct way to handle a change of URL for a resource? The server side redirect.
SEOs know redirects very well, everyone else tends to forget it (or, even worse, to decide not to care about it). That’s because redirects are useful for SEO, they let you keep the value of a link pointing to a resource that is going to be moved to a new URL. Redirects let you preserve the link juice, so they must be good for SEO. But they are also very very good for users, because users won’t experience the kind of user journeys I used as example: a 404 page or an irrelevant redirect.
Breadcrumbs are useful for users, who can find out where in the website they are. And so does Google. Breadcrumbs help Google understand the structure of the site and the content. I can’t even tell if breadcrumbs are more important for users or for search engines. The fantastic truth is that it doesn’t matter!
Custom 404 page
This one has really nothing to do with SEO. Afterall, once Google sees the status code 404, it doesn’t even bother to check the content of the page. If it’s 404, it doesn’t exist. Simple as that.
However, this is something that often an SEO will be asked about. But it’s clearly a usability question, not a SEO question.
I could go on and on with this list, but I think these six examples should be enough to understand why SEO and usability overlap so much and so well. So much and so well that in many cases SEO and usability are in fact the very same thing.