I've seen this question but I'm still not convince about the usefulness of those tags. The meta Question itself recognize that the tag could not survive alone in any question which is specifically prohibited by the tag creation page:
... tags that cannot stand alone as the only tag on a question, are not allowed.
so, why should they exist? Also, isn't more useful if the tag instead of identify the symptoms try to identify the causes?
This tag represents an abnormal state of (any) software, something that should not occur or that is not reproducible (unless it's a bug). A crash is simply a result of an error (in loose terms, a problem) and the cause/solution is relative to the technology at hand (meaning that other tags would be more relevant). Error represents another problem... either cause by the user or the program itself but it's more relevant to tag the question with the piece of software causing the error rather than just informing that I had an error.
To put it in simple terms, let consider the following:
- My app crash each time I startup.
- My kernel crash each time I startup.
- My boot crash each time I startup.
- My apache crash each time I startup.
- My ruby application crash each time I startup.
- My php crash each time I execute X script.
Now lets say:
- My app throws error each time I startup.
- My kernel throws error each time I startup.
- My boot throws error each time I startup.
- My apache throws error each time I startup.
- My ruby application throws error each time I startup.
- My php throws error of syntax each time I execute X script.
Each permutation tells that it vaguely describe the problem but I could already find that in the question body/title itself.
BTW, most of SE sites are trying to get rid of those tags:
- Ask Ubuntu (both crash and error)
- Super User (got rid of a similar tag)
- Stack Overflow (error)