Earlier quoted context omitted.
Identifying the technologies behind a web site involves a lot more than looking at Apache's mod_php headers (which you can and should turn off for security reasons). The tools for figuring out what runs a site actually do a really good job by looking for multiple identifying features. Marketers and SEO people use tools like BuiltWith and Wappalyzer (and many others, most of them not free). You may not know about thos…
Thank you for your comment. I was definitely wrong about the different methods used. This is why I love Hacker News. Always nice to learn something. I still think the stats they provide are a bit weird since there is no "unknown" category. If they can't find the backend technology used for 5% of websites, it changes the whole result, and from what I have seen they don't provide this information. But your really nice…
Using your 5% example, supposing that 5% unknown includes no PHP sites, that only brings the PHP percentage down a little. It doesn’t change the main point that PHP dominates by a wide margin.