the statement of "Components are sub-sections of a project. They are used to group issues within a project into smaller parts." would suggest the duplication of an EPIC. How do these two differ?

[Sarah Roberson]

This question is in reference to Atlassian Documentation: Managing components

we are needing to re-evaluate the JIRA setup here in our company and there is many an argument over the component vs Epic within a project structure. What is the suggestion for a component? would it be by a department/ team/ persons responsible for performing tasks or by tasks themselves? If being the latter, what would then be the purpose of an Epic?

[Chris Dunne · Accepted solution]

At the highest level an EPIC is an actual issue type in JIRA, and represents the concept of Epic as described in Scrum. Loosely speaking you can represent your features as epic, and those features are broken down into smaller, more manageable functions called stories. Epics and Stories are issue types, have all the features of issues (can be assigned, have workflows, fields, screens etc).

You can think of components as another dimension for organizing issues in general. In the case of a software project they could be used to represent different layers of your software architecture e.g. UI, middleware, backend. So you can have Epics that affect multiple components and components that are affected by many different epics, stories, and any other type of issue. In some ways it is similar to a tag/label.

But Epics have one additional feature that make them useful. You can have a default assignee associated with a component. This can be Unassigned, the Project Leader, or a Component Lead. The idea here is that when an issue is created (Epic, Story, Bug or whatever), if the component field is set to some value, then the issue is automatically assigned.

Other people use components to mean other things e.g. department, team, customer. So it doesn't have to be a software component.

If you are using Epics to organize your work then there is an explicit hierarchy in your project. The Epic is decomposed into the related stories or tasks needed to implement the Epic. So the Epic contains the breakdown of work items.

Components do not offer this hierarchy and really are used to a) delegate work through auto-assignment and b) allow for categorization of work right across the project.

Hope this helps,

Chris