Are there more than 2 issue types in JIRA(standard issue type and sub-task issue type)? If so which one is an 'Epic'? If not, what issue type is an Epic?

[Morgan Thunder]

If an Epic is just a standard issue type, why does it behave differently? What kind of issue type is it? I can't find a name for it in JIRA documentation.

[Nic Brough -Adaptavist-]

This is slightly confused by the language.  JIRA ships with several issue types (bug, strory, issue, sub-task, etc) and Epic is simply another type.  And you can add more.  I think you're asking about the hierarchy, rather than the "issue types" (This is a matter of wording - issue type means something specific in JIRA-speak)

The answer is that in plain JIRA, the hierarchy is Project, Issue, sub-task.  Epics and Stories both exist at the issue level.

When you add Agile to a plain JIRA, your Epics remain in the same place, but a load more functionality goes in on top, that allows them to cross projects and contain stories.  But they don't really move from the same level as issues.

Oh, and have a look at https://confluence.atlassian.com/display/AGILE/Working+with+Epics

[Morgan Thunder]

Ok- thanks. I was confused as an 'Epic' seems to have been granted a third level above issues and sub-tasks by the Agile plugin. It certainly behaves differently. The language is confusing - you say there are only issues and sub-tasks, but the Atlassian website talks about 'sub-task issues' and 'sub-task issue types' which suggests that sub-tasks are also issues - that all tickets are in fact issues and then there are 'standard' and 'sub-task' types. Semantics I suppose but it did cause some confusion even in processing your reply - which was very helpful! Thanks.

[Nic Brough -Adaptavist-]

Yes, I find the language confusing as well, even the Atlassian stuff mixes up "issue type" (issue type) and "issue type" (standard/subtask). Sub-tasks are indeed issues in their own right, but they always live below a parent issue type and can't be created separately. Epics are also a bit confusing - with Agile, they are still standard issue types, but they behave in a way that makes them have standard issues as children, almost like subtasks.