As seen earlier, issues in JIRA can represent many things ranging from software development tasks to project management milestones. Issue type is what differentiates one kind of issue from another.
Each issue has a type (therefore, the name issue type), which is represented by the issue type field. This lets you know what type of issue it is and also helps you determine many other aspects of it, such as which fields will be displayed for this issue.
The default issue types are great for simple software development projects, but they do not necessarily meet the needs of others. Since it is impossible to create a system that can address everyone's needs, JIRA lets you create your own issue types and assigns them to projects. For example, for a help desk project, you might want to create a custom issue type called ticket. You can create this custom issue type and assign it to the Help Desk project and users will be able to log tickets, instead of bugs, in the system.
Issue...