@Pacerier For that matter, why not a link to php.net? I don't know what the usual practice with respect to external links is.

@MrStatic Right, I'm not questioning the value of having different tags to distinguish between major versions. When PHP 7 comes out, maybe it'll make sense to have a [php5] and a [php7], although since the differences between PHP versions are usually differences in the language itself, that distinction might not matter for Super User's purposes. Like I said, though, in this specific case, saying "PHP 5" doesn't mean much since PHP 5.6 has seen lots of changes since 5.0.

This is what I was thinking as well. I submitted a suggested edit that just removes the version info, although maybe the wiki can still be improved in other ways.