How often have you searched for a fix for a technical problem, found a link, only to find out - often after some unsuccessful cursing - that the text was about version Hammurabi II and the world (and your software) has moved on?
Wouldn’t it be a good thing if you, as a human, or search engines, had a way to determine the usefulness of such a technical article before reading it?
… within your content
Clearly state, ideally right at the start, which version your text is about, you may enter a range here, and give a hint on whether you are sure or unsure if other versions may work.
… and in HTML metatags
Which version a troubleshooting article or a tutorial is about essentially is metadata. Thus, not only should we add the versioning information in the content of a website, but also include it in the metatags. Because metatags only are useful if we all use them in a similar way, I propose the following format:
<meta name="relevant-version" content="4.2.6">
Alternatively, you might want to add a range, e.g.
<meta name="relevant-version" content="min: 4.1.0, max:4.2.9">