This is probably a really silly question for most of you. I’m learning how to re-tag and I was wondering how to determine if a tag is superfluous.
For example, I see a lot of Facebook PHP SDK specific questions come up under the PHP tag. They’re usually tagged appropriately with facebook-php-sdk, but they also use the php tag. Is the extra PHP tag superfluous? In some cases the solution to a particular question is a general PHP error (or something like that), but in other cases the problem is specific to the Facebook SDK.
More important than this specific example — is there criteria for determining when a tag shouldn’t be applied or does it come down to “use your best judgement”? I thought I should ask before re-tagging inappropriately, making everyone’s life harder. Is there some kind of How to Tag tutorial somewhere on Stack Exchange that I’m overlooking?
I realize that tagging should be common sense, but I’m new around here and I don’t want to screw anything up. :-)